Citing an author who changed his name
I would distinguish between narrative and citation. In narrative text, it is best to refer to a person by their current most preferred scientific name. In citation, on the other hand, it is best to provide the information that will best guide lookup of the document in various search and databases.
When the two are not clearly connected, giving a footnote or parenthetical note will help make it clear to the reader that the difference is intended and not accidental, but it is not strictly required.
I agree with the answer above. Cite papers using the names they were published under, and add a footnote or other indication in the narrative tying together the apparently different authors in the citations. I once wasted a lot of time chasing a reference because the paper I got it from used the author's currently preferred scientific name in the bibliography, but the paper was actually published under a different name (the author had changed her scientific name in the meantime). It would have been much better if the citing paper had given the correct name that the paper was published under, with a note explaining that the two names belonged to the same person.