@article{DMGAA_2005_25_1_a2,
     author = {Vogel, Hans-J\"urgen},
     title = {Categories of functors between categories with partial morphisms},
     journal = {Discussiones Mathematicae. General Algebra and Applications},
     pages = {39--87},
     publisher = {mathdoc},
     volume = {25},
     number = {1},
     year = {2005},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DMGAA_2005_25_1_a2/}
}