Gaya APA

Christy, D, T., Swanson, C, P. (1981). Essentials of precalculus mathematics . New York: New York: Harper & Row; 1981..

Gaya MLA

Christy, Dennis, T.., Swanson, Carl, P.. "Essentials of precalculus mathematics". New York: New York: Harper & Row; 1981., 1981. Text.