APA-referens (7:e uppl.)

LEN, E., & YUE, P. (1988). Secondary 2 vocabulary guide and practice. reston Corporation.

Chicago-referens (17:e uppl.)

LEN, Evelyn, och P.S YUE. Secondary 2 Vocabulary Guide and Practice. Singaphore: reston Corporation, 1988.

MLA-referens (9:e uppl.)

LEN, Evelyn, och P.S YUE. Secondary 2 Vocabulary Guide and Practice. reston Corporation, 1988.