@article{GDZPPN001258613,
title = {Fields of tangent sets and Hofmann cones.},
journal = {Semigroup forum},
volume = {33},
year = {1986},
pages = {1-28},
zbl = {0619.22007},
url = {http://dml.mathdoc.fr/item/GDZPPN001258613}
}
Lawson, J.D. Fields of tangent sets and Hofmann cones.. Semigroup forum, Tome 33 (1986) pp. 1-28. http://gdmltest.u-ga.fr/item/GDZPPN001258613/