@article{GDZPPN002349175, title = {Angle Sums of Convex Polytopes.}, journal = {Mathematica Scandinavica}, volume = {20}, year = {1967}, pages = {199-218}, zbl = {0172.23703}, url = {http://dml.mathdoc.fr/item/GDZPPN002349175} }
Perles, M.A.; Shepard, G.C. Angle Sums of Convex Polytopes.. Mathematica Scandinavica, Tome 20 (1967) pp. 199-218. http://gdmltest.u-ga.fr/item/GDZPPN002349175/