https://www.unisys.com/client-education/mcp-clearpath-server...
However you can get into the documentation for free,
NEWP manual, the systems language,
https://public.support.unisys.com/aseries/docs/ClearPath-MCP...
Overall documentation,
The original system back in 1960's,
https://en.wikipedia.org/wiki/Burroughs_Large_Systems