How should I properly cite an author with a variously credited name? I have recently been dealing with an interesting conundrum.  I have several papers written by the same author, but in which the author's name is credited differently.

Some of these articles credit this author as:

Schön, with an umlaut.

Schoen, where the name is written according to the convention of adding "e", where an umlaut cannot be typed.

My citation style would ordinarily place a ---- under duplicate articles by one author, but the typographical variation in the credited names in the journal means that a reader of my references, who has not verified as I have that these articles are by the same person, might have the impression I was citing two different authors.  Equally, I worry that it would be quite inappropriate to alter the style in which the author's name was printed in the original journal.  Is there anyway I can indicate in my references that these are articles by the same person?
I think the appropriate thing to do is to cite each paper with the spelling that the author chose for that paper. In some way, this is no different than when someone publishes first under their maiden name and then under their married name. Or the other way around. Or when they legally change their name for whatever good or poor reason. Let the author of the paper choose what name they want to use, and use that in the reference.

The reasoning for this is that ultimately, a reference is not meant to educate a reader about the subtler points of identifying the author and their history with family names. The point of a reference is to identify a paper, and the paper has after all been published by the author using one and only one spelling of their name, whatever it may have been the day the paper was written/accepted/published.