Gottfried, B. S. (1973). PL/I programmer's reference guide. Quantum.
芝加哥风格引文Gottfried, Byron S. PL/I Programmer's Reference Guide. New York: Quantum, 1973.
MLA引文Gottfried, Byron S. PL/I Programmer's Reference Guide. Quantum, 1973.
警告：这些引文格式不一定是100％准确.