@article{RCM_1985__19_181756,
     author = {R. Routley and V. Routley},
     title = {Negation {And} {Contradiction.}},
     journal = {Revista colombiana de matematicas},
     pages = {201--232},
     publisher = {mathdoc},
     volume = {19},
     year = {1985},
     zbl = {0614.03007},
     url = {http://geodesic.mathdoc.fr/item/RCM_1985__19_181756/}
}