APA
Pyenson L., . (1981). Plant Health Handbook: A Guide to Better Gardening Indoors and Outdoors. Westport, CT: AVI Publishing Company.
Chicago
Pyenson Louis, . 1981. Plant Health Handbook: A Guide to Better Gardening Indoors and Outdoors. Westport, CT: AVI Publishing Company.
Harvard
Pyenson L., . (1981). Plant Health Handbook: A Guide to Better Gardening Indoors and Outdoors. Westport, CT: AVI Publishing Company.
MLA
Pyenson Louis, . Plant Health Handbook: A Guide to Better Gardening Indoors and Outdoors. Westport, CT: AVI Publishing Company. 1981.