The scientific literature makes science possible. But to be useful, this literature must be organized and retrievable; activities that in turn are made possible by assigning reference information to a source. The source can then be cited in a publication, allowing readers to verify the cited information against its source document. In fact, accurate citation and reference information is the glue that holds science together. Although thousands of style manuals provide extensive details on  how  to format references, researchers are not always taught  when  to cite the literature or to appreciate the critical importance of verifying the accuracy of the cited text and its reference information. Here, I consider the  when, what,  and  why  of citing sources and review some common problems with citations and their references. In doing so, I also raise some questions that can, should, or must be raised at the “sight of a cite and its site.”