The PDF standard (since PDF 1.1) has the amusing terminology of “beads” on a “thread” of “articles”. I think “bead” might be better than “line” or “card” or “page” for my card-based hypertext thing (suggesting perhaps its intellectual descent from wampum).
And indeed the meaning in PDF is closely related:
Some types of documents may contain sequences of content items that are logically connected but not physically sequential.
EXAMPLE 1: A news story may begin on the first page of a newsletter and run over onto one or more nonconsecutive interior pages.
To represent such sequences of physically discontiguous but logically related items, a PDF document may define one or more articles (PDF 1.1). The sequential flow of an article shall be defined by an article thread; the individual content items that make up the article are called beads on the thread. Conforming readers may provide navigation facilities to allow the user to follow a thread from one bead to the next.
The beads are “chained” with “N (next) and V (previous) [attributes]”, while they link to their actual contents with “P” for the page object and “R” for the rectangle on the page.
My intent, of course, is to eliminate or ephemeralize the physical sequence entirely, rather than to simply superimpose a secondary sequence on it.