@article{MAN_1996__306_3_165463,
     author = {Dieter Happel and Luise Unger},
     title = {Modules of finite projective dimension and cocovers.},
     journal = {Mathematische Annalen},
     pages = {445--458},
     year = {1996},
     volume = {306},
     number = {3},
     zbl = {0879.16004},
     url = {http://geodesic.mathdoc.fr/item/MAN_1996__306_3_165463/}
}