Re copyright purposes, if it's not your own image but something found on "google images" that you want to embed, is it necessary to cite in some way? Or does the fact that it has a URL suffice? // I think I've answered my own question. Well, anyway, the googlesphere advice is to assume that all images are copyrighted and only use your own unless you contact the creator and get permission.
When we try to pick out anything by itself, we find it hitched to everything else in the Universe.
~ John Muir