What kinds of national guidance documents in references belong to?

Types of references and types of documents. According to GB3469-83 "Document Types and Document Carrier Codes", it is marked with a single letter: monograph M; Newspaper n; Journal j; Patent document p; Compilation g; Ancient books o; Technical standards; Dissertation d; Scientific and technological report; Reference tool k; Search tool w; File b; Tape a; Chart q; Record l; Product sample x; Video tape v; Meeting minutes; Chinese translation test; Music score I; Movie y; Manuscript h; Microfilm u; Slide z; Miniature flat film f; Other e.