diff --git a/libdo.c b/libdo.c
index bd64b78..4b70a30 100644
--- a/libdo.c
+++ b/libdo.c
@@ -1,4 +1,6 @@
 /*
+ This file is part of libdo
+
  Copyright (c) 2018 Shoaib Ahmed
 
  Permission is hereby granted, free of charge, to any person obtaining a copy
diff --git a/libdo.h b/libdo.h
index a424d6e..5d66962 100644
--- a/libdo.h
+++ b/libdo.h
@@ -1,4 +1,6 @@
 /*
+ This file is part of libdo
+
  Copyright (c) 2018 Shoaib Ahmed
 
  Permission is hereby granted, free of charge, to any person obtaining a copy
diff --git a/tests.c b/tests.c
index 30b8eb5..dfc048f 100644
--- a/tests.c
+++ b/tests.c
@@ -1,3 +1,26 @@
+/*
+ This file is part of libdo
+
+ Copyright (c) 2018 Shoaib Ahmed
+
+ Permission is hereby granted, free of charge, to any person obtaining a copy
+ of this software and associated documentation files (the "Software"), to deal
+ in the Software without restriction, including without limitation the rights
+ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ copies of the Software, and to permit persons to whom the Software is
+ furnished to do so, subject to the following conditions:
+
+ The above copyright notice and this permission notice shall be included in all
+ copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ SOFTWARE.
+*/
 #include <stdio.h>
 #include <unistd.h>
 #include <stdlib.h>
diff --git a/testscpp.cpp b/testscpp.cpp
index c4c2004..5889b0e 100644
--- a/testscpp.cpp
+++ b/testscpp.cpp
@@ -1,3 +1,26 @@
+/*
+ This file is part of libdo
+
+ Copyright (c) 2018 Shoaib Ahmed
+
+ Permission is hereby granted, free of charge, to any person obtaining a copy
+ of this software and associated documentation files (the "Software"), to deal
+ in the Software without restriction, including without limitation the rights
+ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ copies of the Software, and to permit persons to whom the Software is
+ furnished to do so, subject to the following conditions:
+
+ The above copyright notice and this permission notice shall be included in all
+ copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ SOFTWARE.
+*/
 #include <vector>
 #include <iostream>
 #include <chrono>