APA-referens (7:e uppl.)

Langan, J. (2002). English skills with readings (5th ed.). McGraw-Hill.

Chicago-referens (17:e uppl.)

Langan, John. English Skills with Readings. 5th ed. Boston: McGraw-Hill, 2002.

MLA-referens (8:e uppl.)

Langan, John. English Skills with Readings. 5th ed. McGraw-Hill, 2002.