Update README.md

Author: stefanneculai

README.md

@@ -215,3 +215,9 @@ Special thanks to everyone who contributed to getting the Froala Design Blocks t
 ## Copyright and license
 
 Code and documentation copyright 2018 [Froala Labs](https://www.froala.com/). Code released under the [Froala Open Web Design License](https://github.com/froala/design-blocks/blob/master/LICENSE).
+
+Graphics license:
+  - shapes: free to use by [Creative Tim](https://www.creative-tim.com/)
+  - photos: free under the creative license from [Pexels](https://www.pexels.com/photo-license/)
+  - illustrations: free under the creative license from [Undraw](https://undraw.co/license)
+  - icons: free under MIT license [FeatherIcons](https://feathericons.com/)