@article{JRAM_1984__346_152594,
     author = {Richard M. Hain and T. Duchamp},
     title = {Primitive elements in rings of holomorphic functions.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {199--220},
     publisher = {mathdoc},
     volume = {346},
     year = {1984},
     zbl = {0513.32004},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1984__346_152594/}
}