After reading the first 100 pages of Book II in Maus,

It interested me to look for more information on the crematoria explained on page 70-72

http://www.jewishvirtuallibrary.org/jsource/Holocaust/augas.html

This page has a real pictures and the blue prints of the crematoria during the holocaust.

http://www.youtube.com/watch?v=x3EeTFtYr5E

is the virtual reconstruction of the Crematoria II described by Vladek.