C Technical Report 111-91: Integrity-Oriented Control Objectives: Proposed Revisions to the TCSEC, October 1991.
You can download it from the following link: https://packetstormsecurity.com/files/download/14026/C-TR-111-91.txt
Source: https://packetstormsecurity.com/files/14026/C-TR-111-91.txt.html