@article{CM_1987__61_1_61_0,
     author = {Ryan, John},
     title = {Hypercomplex algebras, hypercomplex analysis and conformal invariance},
     journal = {Compositio Mathematica},
     pages = {61--80},
     publisher = {Martinus Nijhoff Publishers},
     volume = {61},
     number = {1},
     year = {1987},
     mrnumber = {879189},
     zbl = {0609.32005},
     language = {en},
     url = {http://www.numdam.org/item/CM_1987__61_1_61_0/}
}