APA-referens (7:e uppl.)

Wittenberg, W. (1980). A prescriptive spelling program (Teacher's ed.). Barnell Loft.

Chicago-referens (17:e uppl.)

Wittenberg, William. A Prescriptive Spelling Program. Teacher's ed. Baldwin, N.Y.: Barnell Loft, 1980.

MLA-referens (8:e uppl.)

Wittenberg, William. A Prescriptive Spelling Program. Teacher's ed. Barnell Loft, 1980.