Although the original text of Engikyaku is lost, many of its passages are quoted in "Ruiju Sandaikyaku" (a statute book written in the Heian period) and "Seiji Yoryaku" (examples of political affairs in the Heian period) written by KOREMUNE no Tadasuke to enable present-day students to guess substantial contents of the text.
「延喜格」の原文は残されていないが、『類聚三代格』や惟宗允亮の『政事要略』にその多くが引用されており、その相当部分の内容を窺い知る事が出来る。