Smil, Vaclav. Feeding the world : a challenge for the twenty-first century / Vaclav Smil. - Cambridge, Mass. : MIT Press, c2000. - xxxviii, 360 p. : ill., maps ; 24 cm. Includes bibliographical references (p. [317]-351). ISBN: 0262194325 (alk. paper) LCCN: 99041747 Subjects--Topical Terms: Agricultural productivity.Food supply. LC Class. No.: S494.5.P75 / S55 2000 Dewey Class. No.: 338.1/9