The article details the use of APL programming language in the Soviet Union, particularly for economic planning at institutions like the Scientific Research Computing Center in Leningrad. It mentions the role of CDC installations, showcasing a unique instance of technological exchange during the Nixon-era thaw. There are references to IBM's APL implementations, including APL/360 and the implementation for the IBM 5100 personal computer. The community around APL in the USSR seems closely tied to critical governmental functions, hinting at the significant applications and secretive nature of its use, especially in relation to the nuclear program.