@article{JRAM_1986__368_152844,
     author = {Kay Wingberg},
     title = {On the product formula in {Galois} groups.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {172--183},
     publisher = {mathdoc},
     volume = {368},
     year = {1986},
     zbl = {0608.12011},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1986__368_152844/}
}