@article{701578,
title = {A high-order helicity invariant and the Rokhlin theorem},
booktitle = {Proceedings of the 15th Winter School "Geometry and Physics"},
series = {GDML\_Books},
publisher = {Circolo Matematico di Palermo},
address = {Palermo},
year = {1996},
pages = {[85]-94},
mrnumber = {MR1463511},
zbl = {0897.57008},
url = {http://dml.mathdoc.fr/item/701578}
}
Akhmetiev, Peter M. A high-order helicity invariant and the Rokhlin theorem, dans Proceedings of the 15th Winter School "Geometry and Physics", GDML_Books, (1996), pp. [85]-94. http://gdmltest.u-ga.fr/item/701578/