Doom 3 Easter Egg - Theresa Chasar

At the enpro plant, you come across a pda belonging to Theresa Chasar. Theresa Chasar is a person who helped in episode 4 of the ultimate doom. To find it, you must go through the level like normal untill you reach the part when you see a girl get her head "decapitated" and turned into a lost soul. once you kill it, look around the office for a pda and whala, you found it.