Please include a credit note like
"Photo Copyright RoyaltyFreeImages.net" or similar and a link to http://www.royaltyfreeimages.net when using one of our stock photos.
All photographs are original and not copyright-free images. We grant you a free royalty-free license to download and use these pictures on your websites, blogs and in designs, however copyright is not transferred. Distribution or resale of the images themselves is not permitted, especially not through stock photo related sites.
Common question: Can I download royalty free images for commercial use?
Short answer: Yes. Free of charge.