Lately I have been searching for sources of public domain images in lesser known places. Today I cam across pixnio.com where you can find free to use public domain images.
PIXNIO - Image usage:
Image is in public domain, not copyrighted, no rights reserved, free for any use. You can use picture for any personal and commercial use without the prior written permission and without fee or obligation.
I would recommend you check the site out if you use a lot of images.
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