@article{IM_1981__64_142825,
     author = {S. Batterson and M. Handel and C. Narasimhan},
     title = {Orientation {Reversing} {Morse-Smale} {Diffeomorphisms} of {S2.}},
     journal = {Inventiones mathematicae},
     pages = {345--356},
     publisher = {mathdoc},
     volume = {64},
     year = {1981},
     zbl = {0481.58021},
     url = {http://geodesic.mathdoc.fr/item/IM_1981__64_142825/}
}