Program graphs, an algebra, and their implication for programming
Michael R. Paige · IEEE Transactions on Software Engineering · 1975
Program graphs have been used as a vehicle to focus attention on the structure of a program. A systematic methodology for partitioning a program graph (digraph) to highlight the relationships between program elements is introduced along with an attendant notation. This notation is described in purely mathematical terms in the first section, and then the programming-related implications of this approach are addressed in the second section.