Boettcher, R. R. (1987). Structured programming in COBOL. Holt, Rinehart and Winston.
芝加哥风格引文Boettcher, Robert R. Structured Programming in COBOL. New York: Holt, Rinehart and Winston, 1987.
MLA引文Boettcher, Robert R. Structured Programming in COBOL. Holt, Rinehart and Winston, 1987.
警告：这些引文格式不一定是100％准确.