@incollection{SB_1991-1992__34__137_0,
     author = {Hitchin, Nigel},
     title = {Hyperk\"ahler manifolds},
     booktitle = {S\'eminaire Bourbaki : volume 1991/92, expos\'es 745-759},
     series = {Ast\'erisque},
     note = {talk:748},
     pages = {137--166},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {206},
     year = {1992},
     mrnumber = {1206066},
     zbl = {0979.53051},
     language = {en},
     url = {http://www.numdam.org/item/SB_1991-1992__34__137_0/}
}