@article{CMH_1970__45_139426,
     author = {M.A. Armstrong},
     title = {Collars and {Concordances} of {Topological} {Manifolds.}},
     journal = {Commentarii mathematici Helvetici},
     pages = {119--128},
     publisher = {mathdoc},
     volume = {45},
     year = {1970},
     zbl = {0187.20602},
     url = {http://geodesic.mathdoc.fr/item/CMH_1970__45_139426/}
}