@article{MZ_1972__127_171758,
     author = {Norman Purzitsky},
     title = {Real-Two-Dimensional {Representations} of {Two-Generator} {Free} {Groups.}},
     journal = {Mathematische Zeitschrift},
     pages = {95--104},
     publisher = {mathdoc},
     volume = {127},
     year = {1972},
     zbl = {0226.20051},
     url = {http://geodesic.mathdoc.fr/item/MZ_1972__127_171758/}
}