Stanton, R.B. "The interpretation of graphics and graphic languages" pp144-160

Nake and Rosenfeld (1972) Nake, F. and Rosenfeld, A. "Graphic Languages" Amsterdam: North-Holland Publishing Company 1972.  

Languages mentioned Clowes {1965} Picture grammar PAX {1964} Picture representation language for Cloud Chambers PDL {1970} Picture Description Language PLANNER {1967} Goal-direct LISP dialect PLM {1957} Graphically oriented data retrieval language RAMOS  {1970} Rule-based graphcial analysis system REF-ARF {1970}