@article{AFST_1998_6_7_2_313_0,
     author = {Nakai, Isao},
     title = {The classification of curvilinear angles in the complex plane and the groups of $\pm $ holomorphic diffeomorphisms},
     journal = {Annales de la Facult\'e des sciences de Toulouse : Math\'ematiques},
     pages = {313--334},
     publisher = {Universit\'e Paul Sabatier. Facult\'e des sciences},
     address = {Toulouse},
     volume = {Ser. 6, 7},
     number = {2},
     year = {1998},
     mrnumber = {1656172},
     zbl = {0958.32003},
     language = {en},
     url = {http://www.numdam.org/item/AFST_1998_6_7_2_313_0/}
}