@article{AMBP_1996__3_2_67_0,
     author = {De Salvo, Mario and Freni, Domenico and Lo Faro, Giovanni},
     title = {On the hypergroups with four proper pairs and without scalars},
     journal = {Annales math\'ematiques Blaise Pascal},
     pages = {67--109},
     publisher = {Laboratoires de Math\'ematiques Pures et Appliqu\'ees de l'Universit\'e Blaise Pascal},
     volume = {3},
     number = {2},
     year = {1996},
     mrnumber = {1435317},
     zbl = {0869.20049},
     language = {en},
     url = {http://www.numdam.org/item/AMBP_1996__3_2_67_0/}
}