M.K. SINGH, U.N. VERMA, S.K. PAL, and R. THAKUR, “Efficacy of slow release nitrogen-fertilizers to rice (Oryza sativa) and their residual effect on wheat (Triticum aestivum)”, IJA, vol. 44, no. 1, p. 44_1 , Oct. 2001, doi: 10.59797/ija.v44i1.3472.