@article{JEMS_2015_17_7_a4,
     author = {Vincent Colin and Sheila Sandon},
     title = {The discriminant and oscillation lengths for contact and {Legendrian} isotopies},
     journal = {Journal of the European Mathematical Society},
     pages = {1657--1685},
     publisher = {mathdoc},
     volume = {17},
     number = {7},
     year = {2015},
     doi = {10.4171/jems/542},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/jems/542/}
}