Questioning of The Holocaust

Khamenei is often ranked among "The World's Most Powerful People." As such, if he (and also there are some others) questions The Holocaust, saying "the Holocaust is an event whose reality is uncertain and if it has happened, it's uncertain how it has happened," then I believe, if it's mentioned in this article, Khamenei's should be present in The Holocaust article as well. There should be section in The Holocaust article about the views of the many prominent scholars like Khamenei, who questions The Holocaust or the extent of it.