CSC-STD-002-85: DoD Password Management Guideline, 12 April 1985. (Green Book)
You can download it from the following link: https://packetstormsecurity.com/files/download/13988/CSC-STD-002-85.txt
Source: https://packetstormsecurity.com/files/13988/CSC-STD-002-85.txt.html