This document was not described based on the author's own opinions, but was written using the reference-based method in which explanations were made by citing laws of codes and ethics (conduct), descriptions in national histories and Japanese/Chinese dictionaries.
本書は、著者自身の見解を叙述するのではなく、律令格式や国史の記事、和漢の典籍を引用することによって語らしむ引証主義的方法を採用している。