Edited sentence: Carol Deppe, Breed Your Own Vegetable Varieties: The Gardener's and Farmer's Guide to Plant Breeding and Seed Saving, Chelsea Green Publishing Company, 2000.Edward Beck, A Packet of Seeds Saved by an Old Gardener, 2008.ISBN 1853831506.ISBN 9780559854682.ISBN 9781594742897.ISBN 9781882424580.ISBN 9781882424603.ISBN 9781890132729.Kent Whealy, Garden Seed Inventory: An Inventory of Seed Catalogs Listing All Non-Hybrid Vegetable Seeds Available in the United States and Canada, Seed Savers Exchange, 2005.Mcgrath Mike, Save and sow seeds of your favourite vegetables, Quirk Books (Stati Uniti), 2009.Renee Vellve, Saving the seed: genetic diversity and european agriculture, Londra, Earthscan Publications, 1992.Suzanne Ashworth, Kent Whealy, Seed to Seed: Seed Saving Techniques for the Vegetable Gardener, Seed Savers Exchange, 2002