TY  - BOOK
AU  - Kenneth G.Cassman
AU  - Robert S.Loomis
TI  - Crop ecology: productivity and management in agricultural systems 
PY  - 2013///
CY  - New Delhi, India
PB  - Cambridge University Press
KW  - Agricultural ecology
KW  - sears
KW  - Agricultural systems
N1  - Includes bibliographical references and index
ER  -