1. Bacastow, R.B.; Adams, J.A.; Keeling, C.D.; Moss, D.J.; Whorf, T.P.; Wong, C.S., Atmospheric Carbon Dioxide, the Southern Oscillation, and the Weak 1975 El Niño, Science, vol.210, no.4465, p. 66-8.
Tries to correlate a link between carbon dioxide levels rising in the atmospheric and El Niño. He shows statistics of carbon dioxide levels in weak El Niño year (1975) and tries to explain sea-surface temperature variations.

2. Barnett, T. P., 1984, Part III, A Partial Anatomy of the Southern Oscillation, Monthly Weather Review, v.112, pp. 2388-2400.
This article documents a new ENSO SST index. Correlates SST in the east-central and eastern tropical pacific and ENSO only when data from the most recent decades is used.

3. Chen, W.Y., Assessment of Southern Oscillation sea level pressure indices, 1982, Monthly Weather Review, v. 110, pp. 800-807.
Monthly sea level pressure anomalies at Easter Island, Rapa, Tahiti, and Darwin were studied from 1951-1979. These sea level pressure anomalies to determine lead/lag relationships. The use of Tahiti and Darwin is recommended as a Southern Oscillation Index.

4. Kawamura, A.; McKerchar, A. I.; Spigel, R. H.; Jinno, K., 1998, El Niño, Journal of Hydrology, v.204, pp.168.
Monthly time series of the SOI were analyzed to determine its characteristics. No significant signs of chaotic behavior was found.

5. Loon, H. V., Shea, D.J., 1987, The Southern Oscillation, Part VI Anomalies of Sea Level Pressure on the Southern Hemisphere and of Pacific Sea Surface Temperature during the development of a warm event. Monthly Weather Review, v. 115, pp. 370-379.
Mean three month sea level pressure anomalies were recorded and analyzed. Most of the Southern Hemisphere responds to the Southern Oscillation, especially the Australia-South Pacific sector.

6. Rasmusson, E.M., 1982, Variations in tropical sea surface temperature and surface wind associated with the Southern Oscillation/El Niño, Monthly Weather Review, v.110, pp. 354-384.
The conventional SOI is usually the difference between station pressure representing the opposite centers of the Indonesian-South Pacific differences. SST Anomalies are associated with the SOI.

7. Rasmusson, E.M., 1985, El Niño and variations in climate, American Scientist, vol.73, no.2, p. 168-77
Details the relationship of Southern Oscillation Index and sea-surface temperatures.

8. Ropelenski, C. F., 1987, An extension of the Tahiti-Darwin Southern Oscillation Index, Monthly Weather Review, v. 115, Sep. 1987, pp. 2161-5
The Southern Oscillation is a result of surface pressure differences across the South Pacific. Several of the most widely used indexes are based on Darwin and Tahiti.

9. Stone, R. C., 1996, Prediction of global rainfall probabilities using phases of the Southern Oscillation Index, Nature, v. 384, pp. 252-255.
The ENSO is an interannual variation in global atmospheric and oceanic patterns. Rainfall forecasting is based upon the studies of lag relationships between the SOI, which can help determine ENSO events and future rainfall.

10. Weare, B.C., 1986, An Extension of an El Niño Index, Monthly Weather Review, v. 114, no. 3, pp. 644-649.
The El Niño index is based on the interannual Pacific sea surface temperatures (SST's) for the period between 1949-1973. The analyses were based upon monthly averages.

11. Wright, P.B., 1984, Relationships between indices of Southern Oscillation, Monthly Weather Review, v.112, pp. 1413-1419.
The Southern Oscillation is the pressure difference between the areas of north Australia and the southeast Pacific. The Southern Oscillation's climatic fluctuations may last between 2-7 years.

1.Philander, G.S., 1990: El Niño, and the Southern Oscillation, ISBN, Academic Press, Inc
Explains El Niño and the signs that point to the El Niño. Shows global effects of El Niño on rainfall by geographical region.

2.Philander, S.G.H., 1989, El Niño and La Nina. A vast system of ocean-atmosphere exchanges covering the tropical Pacific, American Scientist, v 77, n 5, P 451
Details the heat exchange between ocean and atmosphere along the equatorial Pacific. Explains the La Nina event following the El Niño event.

3.Philander, S. George, 1992, El Niño. Oceanus, vol 35, p.56.
Details the ENSO event and effects on the global mean precipitation. Examines regional flucuations due to ENSO.

4.Rasmusson, E.M., and J.M. Wallace, Meteorological aspects of the El Ninõ/Southern Oscillation, Science, 1983, V 222, 1195-1202
Examines the pressure changes in the atmospheric conditions due to the ENSO event.

5.Rasmusson, E.M., 1985, El Niño and variations in climate, American Scientist, vol.73, no.2, p. 168-77
Examines the global effects of ENSO events around world.

6.Trenberth, K.E.. "The Definition of El Niño," Bulletin of the American Meteorlogical Society, 1997, vol. 78, pp. 2771-2777
States the changing opinion of what an ENSO event is in modern meteorlogical terms. Explains the differences from the original definition of El Niño.

7.Ulbrich, U.; Graf, H.F.; Kirchner, I., The impact of El Niño- and volcanic forcing on the atmospheric energy cycle and the zonal mean atmospheric circulation, Contributions to Atmospheric Physics, 1995, vol.68, no.1, p. 59-74
Discusses the link between the ENSO, volcanic eruptions and atmospheric cooling.

8.Webster, F., Studying El Niño on a global scale (TOGA), Oceanus, 1984, v27 n2, p. 58-62
Details the ENSO events along South American coast. Shows weak connections along California coast.

9.Webster, P. J., and T. N. Palmer. 1997 The past and future of El Niño. Nature 390 (11 December): 562-564.
Overview of El Niño events in the tropical Pacific Ocean since 1982 andcomparison to the 1997-1998 El Niño, the best modeled and strongestevent predicted in this century.

10.Wooster, W. S., and O. Guillen., Characteristics of El Niño in 1972. Journal of Marine Research., 1974, V 32, p.378-404
Examines the change in pressure along the equatorial Pacific. Details the change in the mean wind field along the same region.

11. Zebiak, S. E., and Cane, M.A., A model ENSO. Monthly Weather Review. 1987, V 115, 2262-2278
Uses a model of ENSO to couple the ocean and atmosphere. Uses equatorial heat content as the main variable of the model.