@article{JLT_2009_19_4_JLT_2009_19_4_a8,
     author = {C. Benson and R. M. Howe and G. Ratcliff },
     title = {Invariant {Polynomials} for {Multiplicity} {Free} {Actions}},
     journal = {Journal of Lie theory},
     pages = {771--795},
     publisher = {mathdoc},
     volume = {19},
     number = {4},
     year = {2009},
     url = {http://geodesic.mathdoc.fr/item/JLT_2009_19_4_JLT_2009_19_4_a8/}
}