एपीए उद्धरण

Parkin, A., & Yorke, R. (1996). COBOL for students (4th ed.). Arnold.

शिकागो स्टाइल उद्धरण

Parkin, Andrew, और Richard Yorke. COBOL for Students. 4th ed. London: Arnold, 1996.

एमएलए उद्धरण

Parkin, Andrew, और Richard Yorke. COBOL for Students. 4th ed. Arnold, 1996.