van Dam, A., D. Evans, "A Compact Data Structure for Storing, Retrieving, and Manipulating Line Drawings"

[AFIPS] Proceedings of the 1967 Spring Joint Compu (1967) [AFIPS] Proceedings of the 1967 Spring Joint Computer Conference, April 18-20, Atlantic City, N. J. SJCC 30  

Languages mentioned DSPL {1967} Display Systems Programming Language PENCIL {1967} Pictorial encoding language