Hubbell, T. (1999). Sams teach yourself Cobol in 24 hours. Sams Pub..
Cita Chicago Style (17a ed.)Hubbell, Thane. Sams Teach Yourself Cobol in 24 Hours. Indianapolis, IN: Sams Pub., 1999.
Cita MLA (8a ed.)Hubbell, Thane. Sams Teach Yourself Cobol in 24 Hours. Sams Pub., 1999.
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