@article{qtopos,
	title = "A topos for algebraic quantum theory",
	author = "Chris Heunen and Klaas Landsman and Bas Spitters",
	year = "2009",
	journal ="Communications in mathematical physics",
	volume= 291, 
	number= 1, 
	pages={63--110},
	url = "http://arxiv.org/abs/0709.4364",
        doi = "	10.1007/s00220-009-0865-6"
}