Install libbg2-doc by entering the following commands in the terminal:
sudo apt update sudo apt install libbg2-doc
Description:
BG Libraries Collection (documentation)
This package contains a collection of libraries written by Bruce Guenter and put in use in various packages. . The library collection is mandatory to build most of software packages available at http://untroubled.org. . This package contains the documentation for bglibs.
Homepage: http://untroubled.org/bglibs/
Version: 2.04+dfsg-1
Section: universe/doc