Pervin, S.; Hoqlle, M. S.; Iahiruddin, M.; Mian, M. H. ?EFFECTS OF UREA, AZOLLA AND SESBANIA INCORPORATION ON THE CONCENTRA- TION AND UPTAKE OF N, P, K AND S IN RICE (ORYZA SATIVA). Pakistan Journal of Scientific & Industrial Research 1999, 42, 145-149.