Rovner, Paul D. and Henderson, D. Austin. "On the implementation of AMBIT/G: a graphical programming language."

[IJCAI-69] (1969) Donald E. Walker, Lewis M. Norton (Eds.): Proceedings of the 1st International Joint Conference on Artificial Intelligence IJCAI-69, Washington, DC, May 1969. William Kaufmann, 1969  

Languages mentioned AMBIT/G {1968} Ambit symbolic package for graphs LEAP {1968} Language for the Expression of Associative Procedures LEAP {1970} LEAP with Graphical Extensions {1969} LEAP with graphics primitives