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Source: http://travelhdwallpapers.com/mount-kilimanjaro-masai-mara/

Not citing the source of photos(images) is plagiarism. Here is a post on why this is bad, and here is how easy it is to find allowed photos.

Creative Commons: If you are posting content under a Creative Commons license, please attribute and link according to the specific license. If you are posting content under CC0 or Public Domain please consider noting that at the end of your post.

Not indicating that the content you copy/paste is not your original work could be seen as plagiarism.

If you are actually the original author, please do reply to let us know!

That is not the source of it actually. I know the OP, He is from Reddit. Even the link you posted about is just a mirror. And personal photos aren't licensed afaik. You just need a personal consent afaik. Please dont post HD wallpaper websites as sources.....we all know very well they didnt take the pic. If you need more substantial proof send me an e-mail or open an issue. Cheers