@article{MM2_1994__85_3-4_156012,
     author = {Detlev W. Hoffmann},
     title = {The {Newton} polygon of a product of power series.},
     journal = {Manuscripta mathematica},
     pages = {109--118},
     publisher = {mathdoc},
     volume = {85},
     number = {3-4},
     year = {1994},
     zbl = {0827.13009},
     url = {http://geodesic.mathdoc.fr/item/MM2_1994__85_3-4_156012/}
}