EDWARDS, P. (1986). Cobol: A systems and structured approach. Burgess Communications.
Chicago-viite (17. p.)EDWARDS, Perry. Cobol: A Systems and Structured Approach. Minnesota: Burgess Communications, 1986.
MLA-viite (9. p.)EDWARDS, Perry. Cobol: A Systems and Structured Approach. Burgess Communications, 1986.
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