Hans Aberg wrote:
> In the past, it was mentioned literature describing (traditional)
> typesetting rules of mathematics. But unfortunately, I did not copy
> those references, and from time to time, I encounter people who want
> to know.
> Could somebody be kind and indicate some references to such
> literature to me?
>   Hans Aberg

I would like to add to the list of Barbara Beeton

DIN Deutsches Institut fur Normung e.V. (ed.)
Formelzeichen, Formelsatz, Mathematische Zeichen und Begriffe
Berlin, Wien, Zurich: Beuth 1994 (2nd edition = DIN-Taschenbuch 202)

Ok it's german ;-) but nevertheless when typesetting in old Europe and
especially in Germany it is often required to follow DIN.

There're (old) german books on typesetting that have chapters on
mathematics like the "Handbook for Typesetters" by Friedrich Bauer (I
got the 2nd edition of 1941).

Best regards,
Ulrich Dirr