lack of page numbering

What do you put in a reference when the page lacks numbering? Is there any abbreviation to denote such a case? I'm working on some manuscripts that are numbered only on the front side. I refer to them as folium, abbreviated fol. Unfortunately, some of the sheets aren't numbered at all(???)

Solution 1:

The Chicago Manual of Style provides a list of abbreviations used in scholarly works.

n.p. stands for no place, no publisher, no page (presumably whichever one is missing).

Solution 2:

Two examples of page references from manuscripts from a book I have at hand (Thomas, Religion & the Decline of Magic):

E. Bulkeley, A sermon (1586), sig. B4v. [referring to the verso side of the fourth sheet in the second signature of a bound manuscript]

Ely D.R., B 2/15, f. 4v [verso side of fourth sheet (f=folium); I assume this is for unbound papers, volume 2 of 15 (B=Band??), not sure]