@article{MM2_1975__16_154350,
     author = {Larry Siebenmann},
     title = {Chapman's {Classification} of {Shapes.} {A} {Proof} {Using} {Collapsing.}},
     journal = {Manuscripta mathematica},
     pages = {373--384},
     publisher = {mathdoc},
     volume = {16},
     year = {1975},
     zbl = {0314.55012},
     url = {http://geodesic.mathdoc.fr/item/MM2_1975__16_154350/}
}