GRAUER, R. T. (1991). Cobol: From micro to mainframe volume II. Prentice Hall.
Lua i Stíl Chicago (17ú heag.)GRAUER, Robert T. Cobol: From Micro to Mainframe Volume II. London: Prentice Hall, 1991.
Lua MLA (9ú heag.)GRAUER, Robert T. Cobol: From Micro to Mainframe Volume II. Prentice Hall, 1991.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.