@article{CMH_1963__38_139271,
     author = {J\"urg R\"atz},
     title = {Invariante {Funktionen} \"uber teilgeordneten algebraischen {Halbstrukturen.}},
     journal = {Commentarii mathematici Helvetici},
     pages = {121--162},
     publisher = {mathdoc},
     volume = {38},
     year = {1963},
     zbl = {0163.05703},
     url = {http://geodesic.mathdoc.fr/item/CMH_1963__38_139271/}
}