Cita APA

Porcella, R. L., & Zwitzer, J. C. (1989). Catalogue of U.S. Geological survey strong-motion records, 1987. Washington: U.S. Geological Survey.

Citación estilo Chicago

Porcella, Ronald L., y Josephine C. Zwitzer. Catalogue of U.S. Geological Survey Strong-motion Records, 1987. Washington: U.S. Geological Survey, 1989.

Cita MLA

Porcella, Ronald L., y Josephine C. Zwitzer. Catalogue of U.S. Geological Survey Strong-motion Records, 1987. Washington: U.S. Geological Survey, 1989.