https://writing.bobdoto.computer/using-diaries-and-journals-as-source-material-for-zettelkasten-notes/
Additional commentary at r/Zettelkasten - Using diaries and journals as source material for zettelkasten notes by Bob Doto
Bob lays out some basic ideas for citing one's personal journal, diaries, notebooks, and other non-published writing for use in a Luhmann-artig zettelkasten. While he focuses on the scale of the mechanics of citation of one's own notes in other forms, what he's really doing is giving people explicit permission to overlap traditions to more easily use their work from other places in their zettelkasten.
Compare this with Scott Scheper's related article on 2023-05-24 at https://www.reddit.com/r/antinet/comments/13qzgjs/connecting_a_zettelkasten_to_a_commonplace_book/ (and the related YouTube video in which he talks about giving things an "address".
Unmentioned is that in many citation managers, one would likely use a "manuscript" format for citations here. Upon checking it looks like Zotero doesn't have data fields for page number, paragraph, or line numbers for their manuscript type.