@article{MZ_1986__193_173809,
     author = {Ravi S. Kulkarni},
     title = {Geometry of {Free} {Products.}},
     journal = {Mathematische Zeitschrift},
     pages = {613--624},
     publisher = {mathdoc},
     volume = {193},
     year = {1986},
     zbl = {0584.20016},
     url = {http://geodesic.mathdoc.fr/item/MZ_1986__193_173809/}
}