@article{MOMA_1986__102_178294,
     author = {Rudolf Lidl and Winfried B. M\"uller},
     title = {On {Commutative} {Semigroups} of {Polynomials} with {Respect} to {Composition.}},
     journal = {Monatshefte f\"ur Mathematik},
     pages = {139--154},
     publisher = {mathdoc},
     volume = {102},
     year = {1986},
     zbl = {0593.13006},
     url = {http://geodesic.mathdoc.fr/item/MOMA_1986__102_178294/}
}