Choice of agricultural technology; five methods for producing - Rotterdam : NEI, 1961 - 70 h. ; láms. ; gráfs. - Alternative techniques of production. Progress report ; 6 . - Alternative techniques of production. Progress report ; 6 . LCCN: 31887 Subjects--Topical Terms: Agricultura--Costos.Agricultura--Innovaciones tecnológicas.Cereales.Mecanización agrícola. Dewey Class. No.: 338.1 / N4