@article{AFM_1972_501-520_a16,
     author = {Pekka Tukia},
     title = {On discrete groups of the unit disk and their isomorphisms},
     journal = {Annales Fennici Mathematici},
     publisher = {mathdoc},
     volume = {501-520},
     year = {1972},
     doi = {10.5186/aasfm.1972.504},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.5186/aasfm.1972.504/}
}