I looked and found one of your images is derived work from a CC2.0 image meaning you need proper attribution.

As well, for future reference. Please reference the image to the page they are embeded in, not to the picture themselves. I don't mean to plug and advertise myself but look at the sourcing technique done in the post here, just for future reference. You do not have to do it like that but you need more than what is done here for images that require attribution, as well if you think an image is derivative work then find the original work to use the license from (not the derived work) as the person with the derived work may be breaking copyright.