APA
Hills L. D., . (1989). Month-by-month organic gardening. : Thorsons Publishing Group.
Chicago
Hills Lawrence D, . 1989. Month-by-month organic gardening. : Thorsons Publishing Group.
Harvard
Hills L. D., . (1989). Month-by-month organic gardening. : Thorsons Publishing Group.
MLA
Hills Lawrence D, . Month-by-month organic gardening. : Thorsons Publishing Group. 1989.