What is ADAMINT?
Where I find the documentation or the development guide?
When Adabas was first released (1973,1974) the only way to access Adabas was via Direct Calls.
ADAMINT (which stands for Adabas Macro INTerface) was released somewhere around 1975-1976. It was an adaptation of an interface developed by Shell Oil. The idea was to simplify the effort required by the programmers who only had Direct Calls to work with.
Shortly after Adamint was released, Natural 1 was made available. Natural was far easier to work with when compared with Adamint. Basically, shops quickly replaced their adamint modules with Natural. There were holdouts (shops staying with Adamint).
I do not know if Adamint is still supported; check with your local SAG rep.
I believe SAG stopped supporting ADAMINT in the early to mid-1990’s. I was working at one of the “hold out” sites around 1995 when the DBAs started preventing new development with ADAMINTs and strongly encouraged converting programs that still used them. Mostly these programs were large COBOL programs that no one had time to rewrite in Natural. When the head DBA finally set a 1-year deadline, a decision was made to convert the individual ADAMINT calls to the new ADABAS Native SQL calls. After the conversion the DBA pulled the modules that supported ADAMINT from the ADABAS nucleus build JCL and they never went back. I can’t believe the necessary ADAMINT modules are included in or even compatible with any ADABAS version since v5 or maybe v6.
If you are in a situation needing to convert existing programs using ADAMINT calls on a long out-of-support ADABAS system, you could use the current Direct Calls manual (and maybe an IBM Assembler language/macro manual) to help understand the ADAMINT calls since they are mostly a 1-to-1 relationship. Also, assuming you have the source code, the pre-processor and assembly/compile steps for each ADAMINT macro produce voluminous comments about the use of each macro and the parameters required.
If the customer is requesting new development with ADAMINTs, I suggest run away fast! 
I don’t know if SAG keeps an archive of ancient manuals, but as Steve suggested, check with your SAG rep. I don’t think they were creating PDF versions of manuals back then.
Good luck,
George
Also…
Interesting what you can find doing a search of the Tech Community archives. See the last post by Douglas Kelly here:
Also GOOGLE is occasionally helpful. See Treehouse Software Blog entry; apparently founder and president developed ADAMINT.