APA (7e ed.) Bronvermelding

Budlong, M. (2000). SAMS Teach Yourself COBOL in 21 Days (3. Ed.). SAMS.

Chicago (17e ed.) Bronvermelding

Budlong, Mo. SAMS Teach Yourself COBOL in 21 Days. 3. Ed. Indianapolis, Ind.: SAMS, 2000.

MLA (8e ed.) Bronvermelding

Budlong, Mo. SAMS Teach Yourself COBOL in 21 Days. 3. Ed. SAMS, 2000.