@article{IM_1974__25_142292,
     author = {H.W. Jr. Lenstra},
     title = {Rational {Functions} {Invariant} under a {Finite} {Abelian} {Group.}},
     journal = {Inventiones mathematicae},
     pages = {299--325},
     publisher = {mathdoc},
     volume = {25},
     year = {1974},
     zbl = {0292.20010},
     url = {http://geodesic.mathdoc.fr/item/IM_1974__25_142292/}
}