Billington, L. E. (1950). Word power through spelling. Silver Burdett Company.
Chicagoスタイル(17版)引用形式Billington, Lillian E. Word Power Through Spelling. New York, Chicago, Dallas, San Francisco: Silver Burdett Company, 1950.
MLA(8版)引用形式Billington, Lillian E. Word Power Through Spelling. Silver Burdett Company, 1950.
警告: この引用は必ずしも正確ではありません.