@article{10_4064_cm109_1_5,
     author = {Ewa Koz{\l}owska-Walania},
     title = {On commutativity and ovals for a pair of
 symmetries of a {Riemann} surface},
     journal = {Colloquium Mathematicum},
     pages = {61--69},
     publisher = {mathdoc},
     volume = {109},
     number = {1},
     year = {2007},
     doi = {10.4064/cm109-1-5},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm109-1-5/}
}