A case file contains several interrelated documents. The directory within the volume is the directory that describes these files. The case file catalog is a catalog that describes all the case files in a certain storage unit. \x0d\You can refer to the definition in GB/T11822-2008 "General Requirements for the Composition of Scientific and Technical Archives": \x0d\Dossier: an archives storage unit composed of several interconnected documents. \x0d\File directory in a volume: A table that registers file names and other characteristics in a volume and fixes the order of files. It is arranged before the files in the volume. Hereinafter referred to as the directory in the volume. \x0d\Case File Directory: A file directory where the title, file number, storage period and other characteristics of the case file are recorded and arranged in the order of the case file number. \x0d\There are also proofs in the appendix of the standard.