逸いっ書しょ

noun

lost book; missing book

Refers to a book or written work that has been lost or is no longer extant, often used in historical or bibliographic discussions.

• その逸いっ書しょの内ない容ようは、後こう世せいの引いん用ようから部ぶ分ぶん的てきに知しられている。

  The contents of that lost book are partially known from later citations.