Cita APA (7a ed.)

Gies, F., & Gies, J. (1994). Cathedral, forge, and waterwheel: Technology and invention in the Middle Ages. HarperCollins Publishers.

Cita Chicago Style (17a ed.)

Gies, Frances, y Joseph Gies. Cathedral, Forge, and Waterwheel: Technology and Invention in the Middle Ages. New York: HarperCollins Publishers, 1994.

Cita MLA (9a ed.)

Gies, Frances, y Joseph Gies. Cathedral, Forge, and Waterwheel: Technology and Invention in the Middle Ages. HarperCollins Publishers, 1994.