1. IMD 1971Rainfall and drought in India. India Meteorological Department Publication, pp. 22-23
2. Meteorological Monographs, Synoptic Meteorology 1/1976;Y P Rao,1976
3. Shukla J 1986 Interannual variability of monsoon; inMonsoons (eds) J S Fein and P L Stephens (New York: Wiley-Interscience)