APA Citation

HELSON, A. L., & Folley, K. W. (1956). Plane trigcometry (Ed. 3.). New York: Harper & Boother.

Chicago Style Citation

HELSON, Alfred L., and Karl W. Folley. Plane Trigcometry. Ed. 3. New York: Harper & Boother, 1956.

MLA Citation

HELSON, Alfred L., and Karl W. Folley. Plane Trigcometry. Ed. 3. New York: Harper & Boother, 1956.

Warning: These citations may not always be 100% accurate.