APA (7e ed.) Bronvermelding

Billington, L. E. (1950). Word power through spelling. Silver Burdett Company.

Chicago (17e ed.) Bronvermelding

Billington, Lillian E. Word Power Through Spelling. New York, Chicago, Dallas, San Francisco: Silver Burdett Company, 1950.

MLA (8e ed.) Bronvermelding

Billington, Lillian E. Word Power Through Spelling. Silver Burdett Company, 1950.