Kupec, Ivy; Colgan, Chuck (5 April 2007). "Understanding el Niño". Rosenstiel School of Marine and Atmospheric Science. Archived from the original on 21 September 2014. Retrieved 7 December 2017.
Kupec, Ivy; Colgan, Chuck (5 April 2007). "Understanding el Niño". Rosenstiel School of Marine and Atmospheric Science. Archived from the original on 21 September 2014. Retrieved 7 December 2017.