Issue is widely used to mean a single release of a
periodical: a daily, weekly, monthly, or quarterly instalment of
a newspaper or magazine is an issue; the collected issues
of (usually) a year together form a volume.
In bibliography, however,
issue has a more precise meaning: it is a ???.
Issue shouldn't be confused with edition, printing/a>, or state.
From the Guide to Literary Terms by Jack Lynch.
Please send comments to Jack Lynch.
Note: This guide is still in the early stages of development.
Three question marks mean I have to write more on the subject. Bear with me.