In the 1970s and 1980s my primary language was COBOL, initially on a UNIVAC 1100 mainframe, then a Data General Eclipse, but mostly on the HP 3000 mini computer. Here is some of the documentation that I wrote to accompany the software that I designed and developed:

1 COBOL Programming Standards
2 Library of Standard COBOL Macros
3 Library of Standard Utilities
4 Menu and Security System - Functional Specification
5 Menu and Security System - User Manual
6 Menu and Security System - Application Integration
7 Project Development Standards