@article{CMUC_1966__7_4_a8,
     author = {DeMarr, Ralph E. and Fleischer, Isidore},
     title = {Metric spaces over partially ordered semi-groups},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {501--508},
     publisher = {mathdoc},
     volume = {07},
     number = {4},
     year = {1966},
     mrnumber = {0203685},
     zbl = {0142.20902},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1966__7_4_a8/}
}