@article{MS2_1977__41_166551,
     author = {Paul Sarreither},
     title = {Zur algebraischen {Vielfachheit} eines {Produktes} von {Operatorscharen.}},
     journal = {Mathematica Scandinavica},
     pages = {185--192},
     year = {1977},
     volume = {41},
     zbl = {0372.47008},
     url = {http://geodesic.mathdoc.fr/item/MS2_1977__41_166551/}
}