APA način citiranja (7. izdanje)

Kleefstra, W. J. (1980). The concept of data model in database systems. s.n.].

Čikaški stil citiranja (17. izdanje)

Kleefstra, Willem Johannes. The Concept of Data Model in Database Systems. [S.l.: s.n.], 1980.

MLA način citiranja (8. izdanje)

Kleefstra, Willem Johannes. The Concept of Data Model in Database Systems. s.n.], 1980.