Cita APA

Engelken, R., Engelken, R., & Slattery, P. (1981). The art of natural farming & gardening. Barrington Hall Press.

Citación estilo Chicago

Engelken, Ralph, Rita Engelken, and Pat Slattery. The Art of Natural Farming & Gardening. Greeley, Iowa: Barrington Hall Press, 1981.

Cita MLA

Engelken, Ralph, et al. The Art of Natural Farming & Gardening. Barrington Hall Press, 1981.