I guess this could be related to the dialect of the bibtex file. If it is BibTeX, then org-cite-basic--parse-bibtex finds conference and masterthesis for me, and probably anything defined in bibtex-entry-alist. Things that are not in that list would probably be ignored. This is outsourced to bibtex.el.
#+BEGIN_SRC emacs-lisp
(mapcar 'car bibtex-entry-alist)
#+END_SRC
#+RESULTS:
| Article | InProceedings | Conference | InCollection | InBook | Proceedings | Book | Booklet | PhdThesis | MastersThesis | TechReport | Manual | Unpublished | Misc |
if the file has a biblatex dialect then these are the entries that can be parsed.
#+BEGIN_SRC emacs-lisp
(mapcar 'car bibtex-biblatex-entry-alist)
#+END_SRC
#+RESULTS:
| Article | Book | MVBook | InBook | BookInBook | SuppBook | Booklet | Collection | MVCollection | InCollection | SuppCollection | Dataset | Manual | Misc | Online | Patent | Periodical | SuppPeriodical | Proceedings | MVProceedings | InProceedings | Reference | MVReference | InReference | Report | Software | Thesis | Unpublished |
If you open your bibtex file and type C-h v bibtex-dialect, or check that in the Entry-Types menu you can see what the dialect is.
John
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Professor John Kitchin (he/him/his)
Doherty Hall A207F
Department of Chemical Engineering
Carnegie Mellon University
Pittsburgh, PA 15213
412-268-7803