@article{GDZPPN002105179,
title = {A global invariant for three dimensional CR-manifolds.},
journal = {Inventiones mathematicae},
volume = {93},
year = {1988},
pages = {333-348},
zbl = {0643.32006},
url = {http://dml.mathdoc.fr/item/GDZPPN002105179}
}
Burns, D.M. Jr.; Epstein, C.L. A global invariant for three dimensional CR-manifolds.. Inventiones mathematicae, Tome 93 (1988) pp. 333-348. http://gdmltest.u-ga.fr/item/GDZPPN002105179/