@book{AST_1994__224_,
     author = {Collectif},
     title = {Index theorem for elliptic pairs},
     series = {Ast\'erisque},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {224},
     year = {1994},
     zbl = {0856.58037},
     language = {mul},
     url = {http://archive.numdam.org/item/AST_1994__224_/}
}