Cromwell, Elizabeth Seed diffusion mechanism in small farmer communities : lessons from Asia, Africa and Latin America / Elizabeth Cromwell - London : ODI , 1990 - 57p. : ILL. ; 15 cm. - AAU. Research and Extension Network Paper No. 21 . Includes bibliographical references and index. Subjects--Topical Terms: Seedscommunities Gov. Doc. Class. No.: GB ODI AAU NP-21