The protocol features implemented by endpoint systems and their adjacent switches are described in these ATM Forum documents:
"ATM User-Network Interface Specification Version 3.1." 1994.
"ATM Forum Traffic Management Specification Version 4.0." 1996.
The ITU-T I series includes a very large number of documents that relate to ATM.
For a detailed description of ATM networks and ATM protocols, see
Feit, S. Wide Area High Speed Networks. Indianapolis, IN: Macmillan Technical Publishing, 1998.