Library => the doors are closed until you fulfill the "smelling lava" quest one librarian has given you. After you have done this - you can visit the head librarian in the closed north room and get a key for the south room.


http://beyond.divinedivinity.net/help/act3_temple_district.htm

number 28 on this map link shows the crypt entry <img src="/ubbthreads/images/graemlins/winkwink.gif" alt="" />
Kiya