@article{SF_1988__37_1_134930,
     author = {Denis Th\'erien},
     title = {On the equation xt- {\guillemotright} xt+q in categories.},
     journal = {Semigroup forum},
     pages = {265--272},
     publisher = {mathdoc},
     volume = {37},
     number = {1},
     year = {1988},
     zbl = {0641.18002},
     url = {http://geodesic.mathdoc.fr/item/SF_1988__37_1_134930/}
}