@article{CMUC_1986__27_4_a9,
     author = {Kol\'a\v{r}, Ivan},
     title = {Covariant approach to natural transformations of {Weil} functors},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {723--729},
     publisher = {mathdoc},
     volume = {27},
     number = {4},
     year = {1986},
     mrnumber = {874666},
     zbl = {0603.58001},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1986__27_4_a9/}
}