@article{10_21136_CMJ_1962_100517,
     author = {Phillips, Ralph S.},
     title = {Semi-groups of positive contraction operators},
     journal = {Czechoslovak Mathematical Journal},
     pages = {294--313},
     publisher = {mathdoc},
     volume = {12},
     number = {2},
     year = {1962},
     doi = {10.21136/CMJ.1962.100517},
     mrnumber = {0146675},
     zbl = {0113.09901},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1962.100517/}
}