@article{10_4153_CJM_1981_103_0,
     author = {Ware, Roger},
     title = {Valuation {Rings} and {Rigid} {Elements} in {Fields}},
     journal = {Canadian journal of mathematics},
     pages = {1338--1355},
     year = {1981},
     volume = {33},
     number = {6},
     doi = {10.4153/CJM-1981-103-0},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1981-103-0/}
}