@article{GDZPPN002065401,
title = {Values of pseudoriemannian sectional cuvature.},
journal = {Commentarii mathematici Helvetici},
volume = {59},
year = {1984},
pages = {319-332},
zbl = {0573.53014},
url = {http://dml.mathdoc.fr/item/GDZPPN002065401}
}
Beem, John K.; Parker, Philipp E. Values of pseudoriemannian sectional cuvature.. Commentarii mathematici Helvetici, Tome 59 (1984) pp. 319-332. http://gdmltest.u-ga.fr/item/GDZPPN002065401/