diff --git a/silkaj/money/history.py b/silkaj/money/history.py
index 897fab14b3a6017205e6b235da7b73a1488baf59..223462570042a1a21810efdc00919ca041b0d25b 100644
--- a/silkaj/money/history.py
+++ b/silkaj/money/history.py
@@ -85,7 +85,7 @@ def transaction_history(
         "Issuers/Recipients",
         f"Amounts {currency_symbol}",
         f"Amounts UD{currency_symbol}",
-        "Comment",
+        "Reference",
     ]
     if csv_file:
         txs_list.insert(0, table_headers)
@@ -135,7 +135,7 @@ def remove_duplicate_txs(received_txs: list, sent_txs: list) -> None:
     """
     Remove duplicate transactions from history
     Remove received tx which contains output back return
-    that we don`t want to displayed
+    that we don't want to displayed
     A copy of received_txs is necessary to remove elements
     """
     for received_tx in list(received_txs):
@@ -191,7 +191,7 @@ def parse_received_tx(
     Convert time into human format
     Assign identities
     Get amounts and assign amounts and amounts_ud
-    Append comment
+    Append reference/comment
     """
     issuers = []
     for received_tx in received_txs:
diff --git a/silkaj/money/transfer.py b/silkaj/money/transfer.py
index f2a2bed115dc27f2190e1b600a5712cee40748e5..e2e013936c5d46891fa820bdf12f3520506e8e0c 100644
--- a/silkaj/money/transfer.py
+++ b/silkaj/money/transfer.py
@@ -43,7 +43,7 @@ from silkaj.constants import (
 from silkaj.money import tools as m_tools
 from silkaj.public_key import gen_pubkey_checksum
 
-MAX_COMMENT_LENGTH = 255
+MAX_REFERENCE_LENGTH = 255
 
 
 # max size for tx doc is 100 lines.
@@ -51,7 +51,7 @@ MAX_COMMENT_LENGTH = 255
 # (2 * IU + 2 * IS + OUT) <= ( MAX_LINES_IN_TX_DOC - FIX_LINES)
 # with IU = inputs/unlocks ; IS = Issuers/Signatures ; OUT = Outpouts.
 MAX_LINES_IN_TX_DOC = 100
-# 2 lines are necessary, and we block 1 more for the comment
+# 2 lines are necessary, and we block 1 more for the reference/comment
 FIX_LINES = 3
 # assuming there is only 1 issuer and 2 outputs, max inputs is 46
 MAX_INPUTS_PER_TX = 46
@@ -111,7 +111,7 @@ relative reference and recipients' pubkeys",
     cls=tools.MutuallyExclusiveOption,
     mutually_exclusive=["recipients", "amounts", "amountsUD", "allsources"],
 )
-@click.option("--comment", "-c", default="", help="Comment")
+@click.option("--reference", "-ref", default="", help="Transfer reference")
 @click.option(
     "--outputBackChange",
     help="Pubkey recipient to send the rest of the transaction: `<pubkey[:checksum]>`",
@@ -128,7 +128,7 @@ def transfer_money(
     allsources: bool,
     recipients: list[str],
     file_path: Path,
-    comment: str,
+    reference: str,
     outputbackchange: str,
     yes: bool,
 ) -> None:
@@ -162,7 +162,7 @@ No transaction sent.",
 
     recipients = list(recipients)
     outputbackchange = check_transaction_values(
-        comment,
+        reference,
         recipients,
         outputbackchange,
         pubkey_amount[0] < sum(tx_amounts),
@@ -178,7 +178,7 @@ No transaction sent.",
                 tx_amounts,
                 recipients,
                 outputbackchange,
-                comment,
+                reference,
             ),
         )
         confirmation_table = table.draw()
@@ -191,7 +191,7 @@ No transaction sent.",
             issuer_pubkey,
             tx_amounts,
             recipients,
-            comment,
+            reference,
             outputbackchange,
         )
 
@@ -207,9 +207,9 @@ def parse_file_containing_amounts_recipients(
     [ABSOLUTE/RELATIVE]
 
     # comment1
-    amount1 recipient1`s pubkey
+    amount1 recipient1's pubkey
     # comment2
-    amount2 recipient2`s pubkey
+    amount2 recipient2's pubkey
     ```
     """
     reference = ""
@@ -290,19 +290,19 @@ def compute_amounts(amounts: list[float], multiplicator: float) -> list[int]:
 
 
 def check_transaction_values(
-    comment: str,
+    reference: str,
     outputAddresses: list[str],
     outputBackChange: str,
     enough_source: bool,
     issuer_pubkey: str,
 ) -> str:
     """
-    Check the comment format
+    Check reference format
     Check the pubkeys and the checksums of the recipients and the outputbackchange
     In case of a valid checksum, assign and return the pubkey without the checksum
     Check the balance is big enough for the transaction
     """
-    checkComment(comment)
+    check_reference(reference)
     # we check output numbers and leave one line for the backchange.
     if len(outputAddresses) > (MAX_OUTPUTS - 1):
         tools.message_exit(
@@ -316,7 +316,7 @@ def check_transaction_values(
     if enough_source:
         pubkey = gen_pubkey_checksum(issuer_pubkey)
         tools.message_exit(
-            f"{pubkey} pubkey doesn`t have enough money for this transaction.",
+            f"{pubkey} pubkey doesn't have enough money for this transaction.",
         )
     return outputBackChange
 
@@ -327,7 +327,7 @@ def gen_confirmation_table(
     tx_amounts: list[int],
     outputAddresses: list[str],
     outputBackChange: str,
-    comment: str,
+    reference: str,
 ) -> list[list]:
     """
     Generate transaction confirmation
@@ -368,7 +368,7 @@ def gen_confirmation_table(
     # display last informations
     if outputBackChange:
         m_tools.display_pubkey(tx, "Backchange", outputBackChange)
-    tx.append(["Comment", comment])
+    tx.append(["Reference", reference])
     return tx
 
 
@@ -413,7 +413,7 @@ def handle_intermediaries_transactions(
     issuers: str,
     tx_amounts: list[int],
     outputAddresses: list[str],
-    Comment: str = "",
+    reference: str = "",
     OutputbackChange: Optional[str] = None,
 ) -> None:
     while True:
@@ -442,7 +442,7 @@ def handle_intermediaries_transactions(
                 tx_amounts,
                 listinput_and_amount,
                 outputAddresses,
-                Comment,
+                reference,
                 OutputbackChange,
             )
             break
@@ -465,7 +465,7 @@ def generate_and_send_transaction(
     tx_amounts: list[int],
     listinput_and_amount: tuple[list[InputSource], int, bool],
     outputAddresses: list[str],
-    Comment: str,
+    reference: str,
     OutputbackChange: Optional[str] = None,
 ) -> None:
     """
@@ -487,7 +487,7 @@ def generate_and_send_transaction(
         tx_amounts,
         listinput_and_amount,
         outputAddresses,
-        Comment,
+        reference,
         OutputbackChange,
     )
     transaction.sign(key)
@@ -508,7 +508,7 @@ def generate_transaction_document(
     tx_amounts: list[int],
     listinput_and_amount: tuple[list[InputSource], int, bool],
     outputAddresses: list[str],
-    Comment: str = "",
+    reference: str = "",
     OutputbackChange: Optional[str] = None,
 ) -> Transaction:
     listinput = listinput_and_amount[0]
@@ -550,7 +550,7 @@ def generate_transaction_document(
         inputs=listinput,
         unlocks=unlocks,
         outputs=listoutput,
-        comment=Comment,
+        comment=reference,
         currency=head_block["currency"],
     )
 
@@ -583,15 +583,15 @@ def generate_output(
         unitbase = unitbase - 1
 
 
-def checkComment(comment: str) -> None:
-    if len(comment) > MAX_COMMENT_LENGTH:
-        tools.message_exit("Error: Comment is too long")
+def check_reference(reference: str) -> None:
+    if len(reference) > MAX_REFERENCE_LENGTH:
+        tools.message_exit("Error: Transfer reference is too long")
     regex = re.compile(
         "^[0-9a-zA-Z\\ \\-\\_\\:\\/\\;\\*\\[\\]\\(\\)\\?\
 \\!\\^\\+\\=\\@\\&\\~\\#\\{\\}\\|\\\\<\\>\\%\\.]*$",
     )
-    if not re.search(regex, comment):
-        tools.message_exit("Error: the format of the comment is invalid")
+    if not re.search(regex, reference):
+        tools.message_exit("Error: the reference format is invalid")
 
 
 def truncBase(amount: int, base: int) -> int:
diff --git a/silkaj/wot/certify.py b/silkaj/wot/certify.py
index acf187f31bc41f50dbb6d3758b282dc3561ee821..be07e9939bf50daaeb931aeddfb2e3f61b42d5ab 100644
--- a/silkaj/wot/certify.py
+++ b/silkaj/wot/certify.py
@@ -91,7 +91,7 @@ def pre_checks(client: Client, issuer_pubkey: str, pubkey_to_certify: str) -> di
         sys.exit("Current identity is not member.")
 
     if issuer_pubkey == pubkey_to_certify:
-        sys.exit("You can`t certify yourself!")
+        sys.exit("You can't certify yourself!")
 
     # Check if the certification can be renewed
     params = bc_tools.get_blockchain_parameters()
diff --git a/tests/unit/money/test_history.py b/tests/unit/money/test_history.py
index 7770d8d8f0f2b3cc2d89ef30bce26a338532b0d5..36fabd75c4a896aca990400d0f2d25d7c5c7afa2 100644
--- a/tests/unit/money/test_history.py
+++ b/tests/unit/money/test_history.py
@@ -181,7 +181,7 @@ def test_prefix(tx_addresses, outputs, occurence, return_value):
 
 relative_amount = str(round(CENT_MULT_TO_UNIT / mock_ud_value, 2))
 csv_reference = (
-    ["Date", "Issuers/Recipients", "Amounts Ğ1", "Amounts UDĞ1", "Comment"],
+    ["Date", "Issuers/Recipients", "Amounts Ğ1", "Amounts UDĞ1", "Reference"],
     [
         arrow.get(111111114).to("local").format(ALL_DIGITAL),
         "CvrMiUhAJpNyX5sdAyZqPE6yEFfSsf6j9EpMmeKvMCWW:DNB",
diff --git a/tests/unit/money/test_transfer.py b/tests/unit/money/test_transfer.py
index 639f2a6db59e13cd382c02e981149f14336d36df..1cba1558976d0b59e69399da7a173e39d4bd0c88 100644
--- a/tests/unit/money/test_transfer.py
+++ b/tests/unit/money/test_transfer.py
@@ -62,7 +62,7 @@ def test_truncBase(amount, base, expected):
         "tx_amounts",
         "outputAddresses",
         "outputBackChange",
-        "comment",
+        "reference",
     ),
     [
         # only one receiver
@@ -81,7 +81,7 @@ def test_truncBase(amount, base, expected):
             [1000],
             ["BFb5yv8z1fowR6Z8mBXTALy5z7gHfMU976WtXhmRsUMh"],
             "",
-            "This is a comment",
+            "This is a reference",
         ),
         # many receivers and backchange
         (
@@ -93,7 +93,7 @@ def test_truncBase(amount, base, expected):
                 "4szFkvQ5tzzhwcfUtZD32hdoG2ZzhvG3ZtfR61yjnxdw",
             ],
             "C1oAV9FX2y9iz2sdp7kZBFu3EBNAa6UkrrRG3EwouPeH",
-            "This is a comment",
+            "This is a reference",
         ),
         # many receivers and outputs
         (
@@ -105,7 +105,7 @@ def test_truncBase(amount, base, expected):
                 "4szFkvQ5tzzhwcfUtZD32hdoG2ZzhvG3ZtfR61yjnxdw",
             ],
             "",
-            "This is a comment",
+            "This is a reference",
         ),
     ],
 )
@@ -115,7 +115,7 @@ def test_gen_confirmation_table(
     tx_amounts,
     outputAddresses,
     outputBackChange,
-    comment,
+    reference,
     monkeypatch,
 ):
     # patched functions
@@ -153,10 +153,10 @@ def test_gen_confirmation_table(
     for outputAddress, tx_amount in zip(outputAddresses, tx_amounts):
         m_tools.display_pubkey(expected, "To", outputAddress)
         m_tools.display_amount(expected, "Amount", tx_amount, mock_ud_value, G1_SYMBOL)
-    # display backchange and comment
+    # display backchange and reference
     if outputBackChange:
         m_tools.display_pubkey(expected, "Backchange", outputBackChange)
-    expected.append(["Comment", comment])
+    expected.append(["Reference", reference])
 
     # asserting
     table_list = transfer.gen_confirmation_table(
@@ -165,7 +165,7 @@ def test_gen_confirmation_table(
         tx_amounts,
         outputAddresses,
         outputBackChange,
-        comment,
+        reference,
     )
     assert table_list == expected
 
@@ -252,7 +252,7 @@ result1 = Transaction(
             condition="SIG(BFb5yv8z1fowR6Z8mBXTALy5z7gHfMU976WtXhmRsUMh)",
         ),
     ],
-    comment="Test comment",
+    comment="Test reference",
 )
 
 
@@ -262,7 +262,7 @@ result1 = Transaction(
         "tx_amounts",
         "listinput_and_amount",
         "outputAddresses",
-        "Comment",
+        "reference",
         "OutputbackChange",
         "result",
     ),
@@ -295,7 +295,7 @@ result1 = Transaction(
                 "DBM6F5ChMJzpmkUdL5zD9UXKExmZGfQ1AgPDQy4MxSBw",
                 "4szFkvQ5tzzhwcfUtZD32hdoG2ZzhvG3ZtfR61yjnxdw",
             ),
-            "Test comment",
+            "Test reference",
             "BFb5yv8z1fowR6Z8mBXTALy5z7gHfMU976WtXhmRsUMh",
             result1,
         ),
@@ -306,7 +306,7 @@ def test_generate_transaction_document(
     tx_amounts,
     listinput_and_amount,
     outputAddresses,
-    Comment,
+    reference,
     OutputbackChange,
     result,
     monkeypatch,
@@ -319,7 +319,7 @@ def test_generate_transaction_document(
         tx_amounts,
         listinput_and_amount,
         outputAddresses,
-        Comment,
+        reference,
         OutputbackChange,
     )
 
@@ -473,7 +473,7 @@ def test_get_list_input_for_transaction(
         "issuers",
         "tx_amounts",
         "outputAddresses",
-        "Comment",
+        "reference",
         "OutputbackChange",
         "expected_listinput_amount",
     ),
@@ -488,7 +488,7 @@ def test_get_list_input_for_transaction(
                 "DBM6F5ChMJzpmkUdL5zD9UXKExmZGfQ1AgPDQy4MxSBw",
                 "4szFkvQ5tzzhwcfUtZD32hdoG2ZzhvG3ZtfR61yjnxdw",
             ],
-            "Test comment",
+            "Test reference",
             "HcRgKh4LwbQVYuAc3xAdCynYXpKoiPE6qdxCMa8JeHat",
             (
                 [
@@ -518,7 +518,7 @@ def test_get_list_input_for_transaction(
             "HcRgKh4LwbQVYuAc3xAdCynYXpKoiPE6qdxCMa8JeHat",
             [350] * 14,  # total 4900, pubkey has 5300
             ["4szFkvQ5tzzhwcfUtZD32hdoG2ZzhvG3ZtfR61yjnxdw"] * 14,
-            "Test comment",
+            "Test reference",
             "HcRgKh4LwbQVYuAc3xAdCynYXpKoiPE6qdxCMa8JeHat",
             (
                 [
@@ -856,7 +856,7 @@ def test_handle_intermediaries_transactions(
     issuers,
     tx_amounts,
     outputAddresses,
-    Comment,
+    reference,
     OutputbackChange,
     expected_listinput_amount,
     monkeypatch,
@@ -878,7 +878,7 @@ def test_handle_intermediaries_transactions(
         issuers,
         tx_amounts,
         outputAddresses,
-        Comment,
+        reference,
         OutputbackChange,
     )
 
@@ -900,7 +900,7 @@ def test_handle_intermediaries_transactions(
             tx_amounts,
             expected_listinput_amount,
             outputAddresses,
-            Comment,
+            reference,
             issuers,
         )
 
@@ -912,7 +912,7 @@ def test_handle_intermediaries_transactions(
         "amountsud",
         "allsources",
         "recipients",
-        "comment",
+        "reference",
         "outputbackchange",
         "yes",
         "confirmation_answer",
@@ -951,7 +951,7 @@ def test_handle_intermediaries_transactions(
             [
                 "DBM6F5ChMJzpmkUdL5zD9UXKExmZGfQ1AgPDQy4MxSBw",
             ],
-            "Test Comment",
+            "Test reference",
             "HcRgKh4LwbQVYuAc3xAdCynYXpKoiPE6qdxCMa8JeHat",
             False,
             "no",
@@ -964,7 +964,7 @@ def test_handle_intermediaries_transactions(
                 "DBM6F5ChMJzpmkUdL5zD9UXKExmZGfQ1AgPDQy4MxSBw",
                 "HcRgKh4LwbQVYuAc3xAdCynYXpKoiPE6qdxCMa8JeHat",
             ],
-            "Test Comment",
+            "Test reference",
             None,
             False,
             "yes",
@@ -977,7 +977,7 @@ def test_handle_intermediaries_transactions(
                 "DBM6F5ChMJzpmkUdL5zD9UXKExmZGfQ1AgPDQy4MxSBw",
                 "HcRgKh4LwbQVYuAc3xAdCynYXpKoiPE6qdxCMa8JeHat",
             ],
-            "Test Comment",
+            "Test reference",
             None,
             False,
             "yes",
@@ -990,7 +990,7 @@ def test_handle_intermediaries_transactions(
                 "DBM6F5ChMJzpmkUdL5zD9UXKExmZGfQ1AgPDQy4MxSBw",
                 "HcRgKh4LwbQVYuAc3xAdCynYXpKoiPE6qdxCMa8JeHat",
             ],
-            "Test Comment",
+            "Test reference",
             None,
             False,
             "yes",
@@ -1002,7 +1002,7 @@ def test_handle_intermediaries_transactions(
             [
                 "DBM6F5ChMJzpmkUdL5zD9UXKExmZGfQ1AgPDQy4MxSBw",
             ],
-            "Test Comment",
+            "Test reference",
             None,
             False,
             "yes",
@@ -1014,7 +1014,7 @@ def test_send_transaction(
     amountsud,
     allsources,
     recipients,
-    comment,
+    reference,
     outputbackchange,
     yes,
     confirmation_answer,
@@ -1069,7 +1069,7 @@ def test_send_transaction(
         amountsud,
         allsources,
         recipients,
-        comment,
+        reference,
         outputbackchange,
         yes,
     )
@@ -1082,7 +1082,7 @@ def test_send_transaction(
             tx_amounts,
             recipients,
             outputbackchange,
-            comment,
+            reference,
         )
     if yes or confirmation_answer == "yes":
         patched_handle_intermediaries_transactions.assert_called_once_with(
@@ -1090,7 +1090,7 @@ def test_send_transaction(
             key_fifi.pubkey,
             tx_amounts,
             recipients,
-            comment,
+            reference,
             outputbackchange,
         )
     elif confirmation_answer == "no":
@@ -1115,7 +1115,7 @@ def construct_args(
     amountsud,
     allsources,
     recipients,
-    comment,
+    reference,
     outputbackchange,
     yes,
 ):
@@ -1135,9 +1135,9 @@ def construct_args(
     for recipient in recipients:
         args_list.append("-r")
         args_list.append(recipient)
-    if comment:
-        args_list.append("--comment")
-        args_list.append(comment)
+    if reference:
+        args_list.append("--reference")
+        args_list.append(reference)
     if outputbackchange is not None:
         args_list.append("--outputBackChange")
         args_list.append(outputbackchange)
@@ -1152,7 +1152,7 @@ def construct_args(
         "tx_amounts",
         "listinput_and_amount",
         "outputAddresses",
-        "Comment",
+        "reference",
         "OutputbackChange",
     ),
     [
@@ -1233,7 +1233,7 @@ def construct_args(
                 "DBM6F5ChMJzpmkUdL5zD9UXKExmZGfQ1AgPDQy4MxSBw",
                 "CtM5RZHopnSRAAoWNgTWrUhDEmspcCAxn6fuCEWDWudp",
             ),
-            "Test comment",
+            "Test reference",
             None,
         ),
         # Wrong tx : 3 amounts for 1 receiver
@@ -1289,7 +1289,7 @@ def test_generate_and_send_transaction(
     tx_amounts,
     listinput_and_amount,
     outputAddresses,
-    Comment,
+    reference,
     OutputbackChange,
     monkeypatch,
     capsys,
@@ -1308,7 +1308,7 @@ def test_generate_and_send_transaction(
         tx_amounts,
         listinput_and_amount,
         outputAddresses,
-        Comment,
+        reference,
         OutputbackChange,
     )
 
@@ -1328,7 +1328,7 @@ def test_generate_and_send_transaction(
         tx_amounts,
         listinput_and_amount,
         outputAddresses,
-        Comment,
+        reference,
         OutputbackChange,
     )
     network.send_document.assert_called_once()
@@ -1338,7 +1338,7 @@ def test_generate_and_send_transaction(
 @pytest.mark.parametrize(
     # issuer_pubkey can be invalid. It is only used for display.
     (
-        "comment",
+        "reference",
         "outputAddresses",
         "outputBackChange",
         "enough_source",
@@ -1391,7 +1391,7 @@ def test_generate_and_send_transaction(
     ],
 )
 def test_check_transaction_values(
-    comment,
+    reference,
     outputAddresses,
     outputBackChange,
     enough_source,
@@ -1400,7 +1400,7 @@ def test_check_transaction_values(
     capsys,
 ):
     result = transfer.check_transaction_values(
-        comment,
+        reference,
         outputAddresses,
         outputBackChange,
         enough_source,
@@ -1414,7 +1414,7 @@ def test_check_transaction_values(
 @pytest.mark.parametrize(
     # issuer_pubkey can be invalid. It is only used for display.
     (
-        "comment",
+        "reference",
         "outputAddresses",
         "outputBackChange",
         "enough_source",
@@ -1489,7 +1489,7 @@ def test_check_transaction_values(
     ],
 )
 def test_check_transaction_values_errors(
-    comment,
+    reference,
     outputAddresses,
     outputBackChange,
     enough_source,
@@ -1498,7 +1498,7 @@ def test_check_transaction_values_errors(
 ):
     with pytest.raises(SystemExit) as pytest_exit:
         transfer.check_transaction_values(
-            comment,
+            reference,
             outputAddresses,
             outputBackChange,
             enough_source,
@@ -1506,10 +1506,10 @@ def test_check_transaction_values_errors(
         )
     assert pytest_exit.type == SystemExit
     display = capsys.readouterr()
-    if comment.find("Wrong_Char_") != -1:
-        assert display.out == "Error: the format of the comment is invalid\n"
-    elif len(comment) > transfer.MAX_COMMENT_LENGTH:
-        assert display.out == "Error: Comment is too long\n"
+    if reference.find("Wrong_Char_") != -1:
+        assert display.out == "Error: the reference format is invalid\n"
+    elif len(reference) > transfer.MAX_REFERENCE_LENGTH:
+        assert display.out == "Error: Transfer reference is too long\n"
     elif "Wrong_Pubkey" in outputAddresses:
         assert display.out.find("Error: bad format for following public key:") != -1
     elif outputBackChange:
@@ -1517,7 +1517,7 @@ def test_check_transaction_values_errors(
             assert display.out.find("Error: bad format for following public key:") != -1
     elif enough_source is True:
         assert (
-            display.out.find("pubkey doesn`t have enough money for this transaction.")
+            display.out.find("pubkey doesn't have enough money for this transaction.")
             != -1
         )