Sen, S P . Nitrogen assimilation and crop productivity / edited by S. P. Sen, Y. P. Abrol and S. K. Sinha. - New Delhi : Associated Publishing , 1978. - xiii, 313p. : figs, table ; 23cm . Includes index ISBN: Rs. 120.00 (Hb) Subjects--Index Terms: BIOCHEMISTRY Dewey Class. No.: 572.54 / SEN/N