@article{PMIHES_1969__37__5_0,
     author = {Atiyah, Michael F. and Singer, Isadore M.},
     title = {Index theory for skew-adjoint {Fredholm} operators},
     journal = {Publications Math\'ematiques de l'IH\'ES},
     pages = {5--26},
     publisher = {Institut des Hautes \'Etudes Scientifiques},
     volume = {37},
     year = {1969},
     mrnumber = {285033},
     zbl = {0194.55503},
     language = {en},
     url = {http://www.numdam.org/item/PMIHES_1969__37__5_0/}
}