@article{01122737,
title = {Positivity of Brownian transition densities.},
journal = {Electronic Communications in Probability [electronic only]},
volume = {2},
year = {1997},
pages = {43-51},
zbl = {0890.60073},
language = {en},
url = {http://dml.mathdoc.fr/item/01122737}
}
Barlow, Martin T.; Bass, Richard F.; Burdzy, Krzysztof. Positivity of Brownian transition densities.. Electronic Communications in Probability [electronic only], Tome 2 (1997) pp. 43-51. http://gdmltest.u-ga.fr/item/01122737/