diff --git a/ppcls/arch/backbone/model_zoo/distilled_vision_transformer.py b/ppcls/arch/backbone/model_zoo/distilled_vision_transformer.py
index 025d36123206d034902fcff14180096f2327dd5b..676a2897c87700a73f7dce0762ebf7bccbe1cdf1 100644
--- a/ppcls/arch/backbone/model_zoo/distilled_vision_transformer.py
+++ b/ppcls/arch/backbone/model_zoo/distilled_vision_transformer.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# Code was heavily based on https://github.com/facebookresearch/deit
+
 import paddle
 import paddle.nn as nn
 from .vision_transformer import VisionTransformer, Identity, trunc_normal_, zeros_
diff --git a/ppcls/arch/backbone/model_zoo/dla.py b/ppcls/arch/backbone/model_zoo/dla.py
index 669055aebb0af54b6ba31907c394ca084b1d3fa1..b1c00b2dc33970ae27911bccec6782ca8be79a47 100644
--- a/ppcls/arch/backbone/model_zoo/dla.py
+++ b/ppcls/arch/backbone/model_zoo/dla.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# Code was based on https://github.com/ucbdrive/dla
+
 import math
 
 import paddle
diff --git a/ppcls/arch/backbone/model_zoo/efficientnet.py b/ppcls/arch/backbone/model_zoo/efficientnet.py
index 22b7fd1d8ce452aa9413cda8719dfb2ca9fe38ec..bd0cffa621f2d32fcb7c3853ccd2a51c42dc328e 100644
--- a/ppcls/arch/backbone/model_zoo/efficientnet.py
+++ b/ppcls/arch/backbone/model_zoo/efficientnet.py
@@ -1,3 +1,19 @@
+# copyright (c) 2021 PaddlePaddle Authors. All Rights Reserve.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Code was based on https://github.com/lukemelas/EfficientNet-PyTorch
+
 import paddle
 from paddle import ParamAttr
 import paddle.nn as nn
diff --git a/ppcls/arch/backbone/model_zoo/ghostnet.py b/ppcls/arch/backbone/model_zoo/ghostnet.py
index 4a16d8a579a1f45ed4279095bccd74131c047ea5..4d338c1de04480e9a899a8aa4ad8d1c14812223e 100644
--- a/ppcls/arch/backbone/model_zoo/ghostnet.py
+++ b/ppcls/arch/backbone/model_zoo/ghostnet.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# Code was based on https://github.com/huawei-noah/CV-Backbones/tree/master/ghostnet_pytorch
+
 import math
 import paddle
 from paddle import ParamAttr
diff --git a/ppcls/arch/backbone/model_zoo/gvt.py b/ppcls/arch/backbone/model_zoo/gvt.py
index 3553073dad8f2110ddaca59a451230c447812bc9..2af7ccf43fe8ada61da861726585b4633db64d30 100644
--- a/ppcls/arch/backbone/model_zoo/gvt.py
+++ b/ppcls/arch/backbone/model_zoo/gvt.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# Code was based on https://github.com/Meituan-AutoML/Twins
+
 from functools import partial
 
 import paddle
diff --git a/ppcls/arch/backbone/model_zoo/hardnet.py b/ppcls/arch/backbone/model_zoo/hardnet.py
index 112dc3dd8fc38f5442285b8a688049b786d9e3b1..fffd3a420eee9ced34235aeff1f00374676c2d4f 100644
--- a/ppcls/arch/backbone/model_zoo/hardnet.py
+++ b/ppcls/arch/backbone/model_zoo/hardnet.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# Code was based on https://github.com/PingoLH/Pytorch-HarDNet
+
 import paddle
 import paddle.nn as nn
 
diff --git a/ppcls/arch/backbone/model_zoo/levit.py b/ppcls/arch/backbone/model_zoo/levit.py
index a7973339b0ae002752a279c0499a8a2bb62d8b21..991f832bb103ef22eaec87266f1bbf210f3708d3 100644
--- a/ppcls/arch/backbone/model_zoo/levit.py
+++ b/ppcls/arch/backbone/model_zoo/levit.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# Code was based on https://github.com/facebookresearch/LeViT
+
 import itertools
 import math
 import warnings
diff --git a/ppcls/arch/backbone/model_zoo/rednet.py b/ppcls/arch/backbone/model_zoo/rednet.py
index 12802d59cbec406b99b86395361100622a6503b0..be84da1efab88b64fde71c05c8e7dc76b2159484 100644
--- a/ppcls/arch/backbone/model_zoo/rednet.py
+++ b/ppcls/arch/backbone/model_zoo/rednet.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# Code was based on https://github.com/d-li14/involution
+
 import paddle
 import paddle.nn as nn
 
diff --git a/ppcls/arch/backbone/model_zoo/regnet.py b/ppcls/arch/backbone/model_zoo/regnet.py
index 549bd1617ed0c16dfc8ff801e505255bd829c36e..dc381cbcc12e85152fe3a0556731061ec42188b8 100644
--- a/ppcls/arch/backbone/model_zoo/regnet.py
+++ b/ppcls/arch/backbone/model_zoo/regnet.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# Code was based on https://github.com/facebookresearch/pycls
+
 from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
diff --git a/ppcls/arch/backbone/model_zoo/repvgg.py b/ppcls/arch/backbone/model_zoo/repvgg.py
index 94b9355eae95fdb78943db82935e1d48efca2f1a..e919a59fe6e00831e6b02a4d3c8b7cc8d8b9c432 100644
--- a/ppcls/arch/backbone/model_zoo/repvgg.py
+++ b/ppcls/arch/backbone/model_zoo/repvgg.py
@@ -1,3 +1,19 @@
+# copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Code was based on https://github.com/DingXiaoH/RepVGG
+
 import paddle.nn as nn
 import paddle
 import numpy as np
diff --git a/ppcls/arch/backbone/model_zoo/resnest.py b/ppcls/arch/backbone/model_zoo/resnest.py
index a414c29f5b9cf21041a50de7b0ed1c804607dc35..88eee8aacc9b678cea68cce1c3f54efa95578e8c 100644
--- a/ppcls/arch/backbone/model_zoo/resnest.py
+++ b/ppcls/arch/backbone/model_zoo/resnest.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# Code was based on https://github.com/zhanghang1989/ResNeSt
+
 from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
diff --git a/ppcls/arch/backbone/model_zoo/swin_transformer.py b/ppcls/arch/backbone/model_zoo/swin_transformer.py
index 8ce810c2f2779ab9f98afc38f720adf8e9b433c6..c783ec6806edf88625481ef800ac322ba8d71e57 100644
--- a/ppcls/arch/backbone/model_zoo/swin_transformer.py
+++ b/ppcls/arch/backbone/model_zoo/swin_transformer.py
@@ -11,7 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-# Reference: https://github.com/microsoft/Swin-Transformer
+
+# Code was based on https://github.com/microsoft/Swin-Transformer
 
 import numpy as np
 import paddle
diff --git a/ppcls/arch/backbone/model_zoo/tnt.py b/ppcls/arch/backbone/model_zoo/tnt.py
index 13e9b5c4a0831b8c87a01cb50b43405fd8481be9..3ccb7575effb623457e92c9a79c2f891c10fbc71 100644
--- a/ppcls/arch/backbone/model_zoo/tnt.py
+++ b/ppcls/arch/backbone/model_zoo/tnt.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# Code was based on https://github.com/huawei-noah/CV-Backbones/tree/master/tnt_pytorch
+
 import math
 import numpy as np
 
diff --git a/ppcls/data/preprocess/ops/operators.py b/ppcls/data/preprocess/ops/operators.py
index e551fb768a2bf694d426f33ca6bf9ea67bca0906..1971e5ea25e01fa40f9f87922fe877b80048b36c 100644
--- a/ppcls/data/preprocess/ops/operators.py
+++ b/ppcls/data/preprocess/ops/operators.py
@@ -1,4 +1,3 @@
-"""
 # Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -12,7 +11,6 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-"""
 
 from __future__ import absolute_import
 from __future__ import division
diff --git a/ppcls/data/preprocess/ops/timm_autoaugment.py b/ppcls/data/preprocess/ops/timm_autoaugment.py
index 2c9b057a20e4f1c8153ac03e7d65429f03cdf5f8..dd2994dac9aed5be398f02bbc07ae66c176911ca 100644
--- a/ppcls/data/preprocess/ops/timm_autoaugment.py
+++ b/ppcls/data/preprocess/ops/timm_autoaugment.py
@@ -11,10 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-"""
-This code implements is borrowed from Timm: https://github.com/rwightman/pytorch-image-models.
-hacked together by / Copyright 2020 Ross Wightman
-"""
+
+# Code was heavily based on  https://github.com/rwightman/pytorch-image-models
 
 import random
 import math