List of citations in Numdam for : On the chaotic behavior and the non-integrability of the four vortices problem
Annales de l'I.H.P. Physique théorique, Volume 55 (1991) no. 2, pp. 707-718.
Annales de l'I.H.P. Physique théorique, Volume 59 (1993) no. 1, pp. 99-115.