@article{PMIHES_1971__40__69_0,
     author = {Lewis A. Coburn and Ronald G. Douglas and David G. Schaeffer and Isadore M. Singer},
     title = {$C^\ast $-algebras of operators on a half-space, {II.} {Index} theory},
     journal = {Publications Math\'ematiques de l'IH\'ES},
     pages = {69--79},
     year = {1971},
     publisher = {Institut des Hautes \'Etudes Scientifiques},
     volume = {40},
     doi = {10.1007/BF02684694},
     mrnumber = {358418},
     zbl = {0241.47027},
     language = {en},
     url = {https://pmihes.centre-mersenne.org/articles/10.1007/BF02684694/}
}