APA (7th ed.) Citation

Stephens, J. R. (1907). The six-chord spiral. Engineering News Publishing Co..

Chicago Style (17th ed.) Citation

Stephens, John Rittenhouse. The Six-chord Spiral. New York: Engineering News Publishing Co., 1907.

MLA (9th ed.) Citation

Stephens, John Rittenhouse. The Six-chord Spiral. Engineering News Publishing Co., 1907.