@article {MR2825345,
    AUTHOR = {Antonyan, Sergey A. and Ju\'{a}rez-Anguiano, Hugo},
     TITLE = {Dimension of proper {$G$}-spaces},
   JOURNAL = {Topology Appl.},
  FJOURNAL = {Topology and its Applications},
    VOLUME = {158},
      YEAR = {2011},
    NUMBER = {15},
     PAGES = {1910--1919},
      ISSN = {0166-8641,1879-3207},
   MRCLASS = {54F45 (54H11 54H15)},
  MRNUMBER = {2825345},
MRREVIEWER = {Fumihiro\ Ushitaki},
       DOI = {10.1016/j.topol.2011.06.034},
       URL = {https://doi.org/10.1016/j.topol.2011.06.034},
}


@article {MR2661569,
    AUTHOR = {Antonyan, Sergey A.},
     TITLE = {Proper actions on topological groups: applications to quotient
              spaces},
   JOURNAL = {Proc. Amer. Math. Soc.},
  FJOURNAL = {Proceedings of the American Mathematical Society},
    VOLUME = {138},
      YEAR = {2010},
    NUMBER = {10},
     PAGES = {3707--3716},
      ISSN = {0002-9939,1088-6826},
   MRCLASS = {22F05 (22A05 54F45 54H11 57S99)},
  MRNUMBER = {2661569},
MRREVIEWER = {Jorge\ Galindo},
       DOI = {10.1090/S0002-9939-2010-10504-X},
       URL = {https://doi.org/10.1090/S0002-9939-2010-10504-X},
}



@article {MR2040583,
    AUTHOR = {Biller, Harald},
     TITLE = {Characterizations of proper actions},
   JOURNAL = {Math. Proc. Cambridge Philos. Soc.},
  FJOURNAL = {Mathematical Proceedings of the Cambridge Philosophical
              Society},
    VOLUME = {136},
      YEAR = {2004},
    NUMBER = {2},
     PAGES = {429--439},
      ISSN = {0305-0041,1469-8064},
   MRCLASS = {57S05 (22F05 37B05 54H15 57S20)},
  MRNUMBER = {2040583},
MRREVIEWER = {Ivan\ Arzhantsev},
       DOI = {10.1017/S0305004103007217},
       URL = {https://doi.org/10.1017/S0305004103007217},
}