Engelken, R., Engelken, R., & Slattery, P. (1981). The art of natural farming & gardening. Barrington Hall Press.
芝加哥风格引文Engelken, Ralph, Rita Engelken, 与 Pat Slattery. The Art of Natural Farming & Gardening. Greeley, Iowa: Barrington Hall Press, 1981.
MLA引文Engelken, Ralph, et al. The Art of Natural Farming & Gardening. Barrington Hall Press, 1981.
警告：这些引文格式不一定是100％准确.