1. Abrol , I. P. , R. Chhabra , and R. K. Gupta , 1980 . A fresh look at the diagnostic criteria for sodic soils, pp , 142 – 147 , in, Proceedings, International Symposium on Salt-affected Soils , Karnal , India .
2. DETERMINATION OF CALCIUM AND MAGNESIUM IN SOIL AND PLANT MATERIAL