GRAPPLE - GRAPh Processing LanguagE. 1968. "A Directed Graph
Representation for Computer Simulation of Belief Systems", L.G. Tesler et
al, Math Biosciences 2:19-40 (1968).
GRAPPLE Programming Language
http://www.programming-languages.co.uk/grapple.html
Large list of computer programming languages arranged alphabetically, with explanations.