@article{JDM_1972__74_146618,
     author = {G.M. Petersen},
     title = {Factor {Sequences} and {Their} {Algebras.}},
     journal = {Jahresbericht der Deutschen Mathematiker-Vereinigung},
     pages = {182--188},
     publisher = {mathdoc},
     volume = {74},
     year = {1972},
     zbl = {0255.40004},
     url = {http://geodesic.mathdoc.fr/item/JDM_1972__74_146618/}
}