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I'm sorry. I was browsing through tumblr and found it without any credits. In future I will give my best to find the content creator before posting first.

If you don't know who the creator was just post a link to where you found it. The important thing is to make it clear that it isn't your work. This is really important when using tags like photography where a lot of users like to post their own work.

Thanks for clarifying. As I said in future I will do my best.