Elshafei, A. (1969). General Purpose Systems Simulator (GPSS). The Institute of National Planning.
Citazione stile Chigago Style (17a edizione)Elshafei, Alwalid. General Purpose Systems Simulator (GPSS). Cairo: The Institute of National Planning, 1969.
Citatione MLA (9a ed.)Elshafei, Alwalid. General Purpose Systems Simulator (GPSS). The Institute of National Planning, 1969.