Unfortunately the search is down right now, so my apologies if this has been answered before.
I'm setting a book for a student group I'm part of. Many of the essays have endnote citations. Is there a hard and fast rule about the amount of spacing that comes after the superscript character and before the next? I can't quite discern if a single space suffices, or if two spaces are necessary.
The text is Sabon 10/12 x 23 if it makes a difference.