1. M. Artin, Grothendieck topologies, seminar notes, Harvard University, Department of Mathematics, 1962.
2. Étale Homotopy;Artin,1969
3. Locally Presentable and Accessible Categories;Adámek,1994
4. Sheafifiable homotopy model categories;Beke;Math. Proc. Cambridge Philos Soc.,2000
5. Handbook of Categorical Algebra. II. Categories and Structures;Borceux,1994