How to format references in a book introduction?

Question

I'm tidying up a project that has some comprehensive book introductions, but I can't figure out how to mark Scripture references that occur within \ip sections. References are given to chapters or sections within the book, or other books, such as "(15:22—16:21)". The Basic Checks flags them as "invalid medial punctuation" errors. I tried \ior ... \ior* as used in the book outline, but this gives a "Marker cannot occur here" error. I could just "deny" those messages or allow the punctuation, but I'd like to have the Scripture reference checking operate on those to make sure they're formatted correctly. What is the correct way to mark references in a book introduction?

Answer 1

We are currently using \xt ...\xt* in our projects for this (and custom.sty to allow it). Maybe \rq ...\rq* is more appropriate: https://ubsicap.github.io/usfm/titles_headings/index.html#rq-rq