1. Mitra, Ind. J. Agric. Sci., 6, 555 (1936).
2. Mukherjee Mitra and Mukherjee, Trans. Nat. Inst. Sci. Ind. 1, No. 10, 227 (1937).
3. Mukherjee and Mitra, Ind. J. Agric. Sci., 12, 433 (1942).
4. Wiegner and Pallmann, Ver. Zwei. Komm. Alkali-subcomm. Internal. Bod. Ges., B, 92 (1929).
5. Unpublished work of S. N. Bagchi.