Budlong, M. (2000). SAMS Teach Yourself COBOL in 21 Days (3. Ed.). SAMS.
Chicago-Zitierstil (17. Ausg.)Budlong, Mo. SAMS Teach Yourself COBOL in 21 Days. 3. Ed. Indianapolis, Ind.: SAMS, 2000.
MLA-Zitierstil (8. Ausg.)Budlong, Mo. SAMS Teach Yourself COBOL in 21 Days. 3. Ed. SAMS, 2000.
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