@article{MAN_1974__208_162561,
     author = {Dietrich Braess},
     title = {Morse-Theorie f\"ur berandete {Mannigfaltigkeiten.}},
     journal = {Mathematische Annalen},
     pages = {133--148},
     publisher = {mathdoc},
     volume = {208},
     year = {1974},
     zbl = {0263.58005},
     url = {http://geodesic.mathdoc.fr/item/MAN_1974__208_162561/}
}