It took a long time searching for the source.
This was earliest source I could find in Google Image Search, which is a great way to track the life of an image. I go to the oldest reference and search from there for copyright information. I did not succeed with this image. My search took me here to tumblr 11 months ago. I love the picture and would like to use it but source it properly. Did you create this?
Let me know how you want attribution if used for educational purposes?