765 ILCS 220/4

An entry book shall be provided by the recorder or Registrar of Deeds for the recordation of a monument record by Illinois Registered Land Surveyors for public land survey corners, as defined by the Manual of Instructions for the Survey of the Public Lands of the United States and accessories to such corner which are found, set, reset or used as a control in any survey by such land surveyor.

The monument records shall be recorded with the recorder or Registrar of Titles and be securely fastened into the entry book as provided for that purpose. The monument records shall be indexed by Section, Township and Range so as to be easily retrievable.