Binary package “udisks2-doc” in ubuntu bionic

udisks2 documentation

 The udisks daemon serves as an interface to system block devices,
 implemented via D-Bus. It handles operations such as querying, mounting,
 unmounting, formatting, or detaching storage devices such as hard disks
 or USB thumb drives.
 .
 This package provides the API reference and manuals in devhelp format.