diff --git a/examples/create_public_key.py b/examples/create_public_key.py
index 67a9b61a2ffa0f001dea62b398330c68834b7c0e..3409bc8bec9d36029b46f2b020a687b6568b0054 100644
--- a/examples/create_public_key.py
+++ b/examples/create_public_key.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import getpass
 from duniterpy.key import SigningKey
 
diff --git a/examples/listen_ws2p.py b/examples/listen_ws2p.py
index 1abb60cc634a2080ccead16369e3c20acc92324a..9861c718adae12732fc795cceccb586e44cc2e0b 100644
--- a/examples/listen_ws2p.py
+++ b/examples/listen_ws2p.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import asyncio
 import json
 import sys
diff --git a/examples/load_binary_encrypted_message.py b/examples/load_binary_encrypted_message.py
index b7c0a7cd121543c75e35319aeb6d7beabd9ac12a..9300efe3301825901cf5b65e062eb977a0669c21 100644
--- a/examples/load_binary_encrypted_message.py
+++ b/examples/load_binary_encrypted_message.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import getpass
 import sys
 
diff --git a/examples/load_binary_signed_message.py b/examples/load_binary_signed_message.py
index ac98c41556a33cd0f8f576c5ebfec39969444817..e842b7d15e1d5f0e6c6da62469e1fe7206edf10c 100644
--- a/examples/load_binary_signed_message.py
+++ b/examples/load_binary_signed_message.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import sys
 
 from duniterpy.key import VerifyingKey
diff --git a/examples/load_cleartext_ascii_armor_message.py b/examples/load_cleartext_ascii_armor_message.py
index 6ce30154ba33499ab02fa7ffe40278fdf4e84a70..34bcc17901bc3607c3e15f3aaecd10d63f487516 100644
--- a/examples/load_cleartext_ascii_armor_message.py
+++ b/examples/load_cleartext_ascii_armor_message.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 from duniterpy.key import AsciiArmor
 
 # CONFIG #######################################
diff --git a/examples/load_credentials_file.py b/examples/load_credentials_file.py
index 48212c64a6296cf6e7b8a336ce8921fc962ec260..f9b1bd90abe3da39f9271c5a19f8f94bcb4b0fd8 100644
--- a/examples/load_credentials_file.py
+++ b/examples/load_credentials_file.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import sys
 
 from duniterpy.key import SigningKey
diff --git a/examples/load_encrypted_ascii_armor_message.py b/examples/load_encrypted_ascii_armor_message.py
index 85b91a8e4540a84650ff760957b76682bedbe20c..6e6ae2bb522b92d29f22f6e507cd3f3818c20ba5 100644
--- a/examples/load_encrypted_ascii_armor_message.py
+++ b/examples/load_encrypted_ascii_armor_message.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import getpass
 
 from duniterpy.key import AsciiArmor, SigningKey
diff --git a/examples/load_scuttlebutt_file.py b/examples/load_scuttlebutt_file.py
index cd6d192c3ed43bd4d405708db6afa06f5ee86584..5fb6840b6e7e5ba62f941cc950b272ad3ee3c55e 100644
--- a/examples/load_scuttlebutt_file.py
+++ b/examples/load_scuttlebutt_file.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import sys
 
 from duniterpy.key import SigningKey
diff --git a/examples/request_data.py b/examples/request_data.py
index 07abf02f73db7fa70919c143dd2922b7bc7edfc0..06f03c6585375dc3738c79089cc5044877df9264 100644
--- a/examples/request_data.py
+++ b/examples/request_data.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import asyncio
 from duniterpy.api.client import Client, RESPONSE_AIOHTTP
 from duniterpy.api import bma
diff --git a/examples/request_data_async.py b/examples/request_data_async.py
index 7e1f1ba90e8d2f44367d9baa0bc301ff57545c79..153a4257a4305506dd2de8028bc28e550606d70d 100644
--- a/examples/request_data_async.py
+++ b/examples/request_data_async.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import asyncio
 
 from duniterpy.api import bma
diff --git a/examples/request_data_elasticsearch.py b/examples/request_data_elasticsearch.py
index 89bcd9ac3f6512f95893c4bc1d62be285f42b262..d767e6afaff261fcc78c2a017b934b414a5a8259 100644
--- a/examples/request_data_elasticsearch.py
+++ b/examples/request_data_elasticsearch.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import asyncio
 
 from duniterpy.api.client import Client
diff --git a/examples/request_web_socket_block.py b/examples/request_web_socket_block.py
index d0ebfa24216ac20b3663e24ece5e0fde3d817a8d..7a3e04e311d10d172c7a1c7b080c3046b6bc34c8 100644
--- a/examples/request_web_socket_block.py
+++ b/examples/request_web_socket_block.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import asyncio
 import json
 from _socket import gaierror
diff --git a/examples/request_ws2p.py b/examples/request_ws2p.py
index 9edc1248aeb61e62cee320881f0e9b8e91f67b9d..b73945a1b86c60d1751cec687892f4cb9fe51e98 100644
--- a/examples/request_ws2p.py
+++ b/examples/request_ws2p.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import asyncio
 import json
 import time
diff --git a/examples/save_and_load_private_key_file.py b/examples/save_and_load_private_key_file.py
index 19fe369845af564d6cea712043b5583d4fa94b21..252a6cec6f906fe440036216a7e0d361dd4481f9 100644
--- a/examples/save_and_load_private_key_file.py
+++ b/examples/save_and_load_private_key_file.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 from duniterpy.key import SigningKey
 import getpass
 import os
diff --git a/examples/save_and_load_private_key_file_ewif.py b/examples/save_and_load_private_key_file_ewif.py
index 55307829818125ad02483765468110f5a393483e..f901c24bb1bc98b669dc2965fcc60702a38aac2c 100644
--- a/examples/save_and_load_private_key_file_ewif.py
+++ b/examples/save_and_load_private_key_file_ewif.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 from duniterpy.key import SigningKey
 import getpass
 import os
diff --git a/examples/save_and_load_private_key_file_pubsec.py b/examples/save_and_load_private_key_file_pubsec.py
index 082f491a5263cfcb972bdca7890dbd85f0a3110c..7394bfd792b700ce8dc7b30abb0af504914eb8e5 100644
--- a/examples/save_and_load_private_key_file_pubsec.py
+++ b/examples/save_and_load_private_key_file_pubsec.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 from duniterpy.key import SigningKey
 import getpass
 import os
diff --git a/examples/save_and_load_private_key_file_wif.py b/examples/save_and_load_private_key_file_wif.py
index 6f069398db8fc00c66754a95a3698f467a61de8b..5427b2eee78caf3ddd74ec8eb31c1b396899f91d 100644
--- a/examples/save_and_load_private_key_file_wif.py
+++ b/examples/save_and_load_private_key_file_wif.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 from duniterpy.key import SigningKey
 import getpass
 import os
diff --git a/examples/save_binary_encrypted_message.py b/examples/save_binary_encrypted_message.py
index 416eccea2203ab6cf24af91b186d65094da854ad..00859ef4928601946c24e5d621c65aeb2a0b1e7a 100644
--- a/examples/save_binary_encrypted_message.py
+++ b/examples/save_binary_encrypted_message.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 from duniterpy.key import PublicKey
 
 # CONFIG #######################################
diff --git a/examples/save_binary_signed_message.py b/examples/save_binary_signed_message.py
index 1b957d0b4b5d702edbee196034f599c6c7f7e39f..3d746945f4a7315a0eb303b656bd9917ddd16faa 100644
--- a/examples/save_binary_signed_message.py
+++ b/examples/save_binary_signed_message.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import getpass
 
 import libnacl.sign
diff --git a/examples/save_cleartext_ascii_armor_message.py b/examples/save_cleartext_ascii_armor_message.py
index 4e8c7950587c63837c506d97f82596f4871b907a..073145c3c8e8326afc85c04c2ce0854be07dace0 100644
--- a/examples/save_cleartext_ascii_armor_message.py
+++ b/examples/save_cleartext_ascii_armor_message.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import getpass
 import sys
 
diff --git a/examples/save_encrypted_ascii_armor_message.py b/examples/save_encrypted_ascii_armor_message.py
index 093b013f4ae6375dc136930191297fbf431fffb3..35f4a435e73283384d42490472e7f88342f1b419 100644
--- a/examples/save_encrypted_ascii_armor_message.py
+++ b/examples/save_encrypted_ascii_armor_message.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import getpass
 from duniterpy import __version__
 
diff --git a/examples/save_revoke_document.py b/examples/save_revoke_document.py
index 4b70bb2bab57b19002f6cb51d5a58cfdeb89542c..62eb80b61a5b98f7bccc2a2f0f43ba0458017568 100644
--- a/examples/save_revoke_document.py
+++ b/examples/save_revoke_document.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import asyncio
 import getpass
 import os
diff --git a/examples/send_certification.py b/examples/send_certification.py
index f62f478e4aa4dfee54b5b5d671f7ab2a50ed96fc..cf325cba4cc9f8b4a8903391fd83864c7c3dc009 100644
--- a/examples/send_certification.py
+++ b/examples/send_certification.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import sys
 import asyncio
 import getpass
diff --git a/examples/send_identity.py b/examples/send_identity.py
index c024a50f12bd8c8a576bb84144589f24a7536293..261274a146c71f32485d70bd926be71cbd3c5032 100644
--- a/examples/send_identity.py
+++ b/examples/send_identity.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import asyncio
 import getpass
 
diff --git a/examples/send_membership.py b/examples/send_membership.py
index 393c0a15343a5de66a6a8969d4058b76d46e0a5a..8fd5b25d4b72127e73532b76a146b57e4dcc1eac 100644
--- a/examples/send_membership.py
+++ b/examples/send_membership.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import asyncio
 import getpass
 
diff --git a/examples/send_transaction.py b/examples/send_transaction.py
index 333abb64ffda3cc786737ae936547df18dffca20..56aaacb5d24bd1a894e321e2bf3b20ef214bf2f5 100644
--- a/examples/send_transaction.py
+++ b/examples/send_transaction.py
@@ -1,3 +1,20 @@
+"""
+Copyright  2014-2020 Vincent Texier <vit@free.fr>
+
+DuniterPy is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+DuniterPy is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
 import sys
 import asyncio
 import getpass