Near-infrared evidence for a sudden temperature increase in Eta Carinae Andrea Mehner, Kazunori Ishibashi, Patricia Whitelock, Takahiro Nagayama, Michael Feast, Francois van Wyk and Willem-Jan de Wit A&A, 564 (2014) A14 Published online: 28 March 2014 DOI: 10.1051/0004-6361/201322729