How do you attribute credit if you don’t know where content comes from?

I’ve added a nice image to my little HTTP status codes application for the famous “teapot” 418 code (http://kodes.ekynoxe.com/k/418), but I couldn’t find any credit for that image anywhere.

Is this image your work? Let me know so I can credit you!!!

Is this image your work? Let me know so I can credit you!!!

Given the emphasis given these days to credit attribution and piracy, I’m wondering how you can trace an image source… Anyone knows?

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