@article{GDZPPN002359316,
title = {Smoothness of vector sums of plane convex sets.},
journal = {Mathematica Scandinavica},
volume = {61},
year = {1987},
pages = {239-252},
zbl = {0617.52004},
url = {http://dml.mathdoc.fr/item/GDZPPN002359316}
}
Kiselman, Christer O. Smoothness of vector sums of plane convex sets.. Mathematica Scandinavica, Tome 61 (1987) pp. 239-252. http://gdmltest.u-ga.fr/item/GDZPPN002359316/