@article{10_4064_sm_26_3_263_272,
     author = {W. Mlak},
     title = {On semi-groups of contractions in {Hilbert} spaces},
     journal = {Studia Mathematica},
     pages = {263--272},
     publisher = {mathdoc},
     volume = {26},
     number = {3},
     year = {1965},
     doi = {10.4064/sm-26-3-263-272},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm-26-3-263-272/}
}