@article{GDZPPN002084821,
title = {Gaps of one dimensional periodic AKNS systems.},
journal = {Forum mathematicum},
volume = {5},
year = {1993},
pages = {459-504},
zbl = {0784.34024},
url = {http://dml.mathdoc.fr/item/GDZPPN002084821}
}
Guillot, Jean-Claude; Grébert, Benoit. Gaps of one dimensional periodic AKNS systems.. Forum mathematicum, Tome 5 (1993) pp. 459-504. http://gdmltest.u-ga.fr/item/GDZPPN002084821/