J. C. GUPTA, B. K. MUKHERJEE, K. N. AGARWAL, and V. P. AHUJA, “VALIDITY OF PREDICION METHODS UNDER POPULATION STRESS IN COMPOSITE AND VARIETAL HYBRIDS IN MAIZE (ZEA MAYS L.)”, IJGPB, vol. 49, no. 01, pp. 73–79, Feb. 1989.