@article{JRAM_1975__277_151621,
     author = {Wayne Bishop},
     title = {A theory of multiplicity for multiplictive filtrations.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {8--26},
     publisher = {mathdoc},
     volume = {277},
     year = {1975},
     zbl = {0311.13008},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1975__277_151621/}
}