Work [primary sources: author, title, incipit/explicit, date, associated person, place of composition]
Library [libraries holding primary sources: city, name of library, shelfmark]
Institution [religious or military order, monastery, convent, church, cathedral, library, archive, university, college, etc.: name, place, date]
Person [biographical information for, e.g., author, previous owner, printer, scribe, publisher, bookbinder, member of nobility or church hierarchy: name, title, date, associated place, profession, religious or military order]
Reference [secondary sources: author, title, date, place of publication, publisher, series, associated person]
MsEd [manuscript or printed edition: city, library, current or former shelfmark, date, place of production, scribe / printer, publisher / patron, previous owner, other associated person]