Jiri Ocenasek Stefan Kern Nikolaus Hansen Petros Koumoutsakos A Mixed Bayesian Optimization Algorithm with Variance Adaptation. 352-361 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3242&spage=352 2004 conf/ppsn/2004 PPSN db/conf/ppsn/ppsn2004.html#OcenasekKHK04