Tunisian Journal of Mathematicsan international publication organized by the Tunisian Mathematical Society

Editors-in-ChiefAhmed Abbes, France

Ali Baklouti, Tunisia

Hajer Bahouri, France Arnaud Beauville, France Bassam Fayad, France Benoit Fresse, France Dennis Gaitsgory, United States Emmanuel Hebey, France Mohamed Ali Jendoubi, Tunisia Sadok Kallel, France & UAE Minhyong Kim, UK & Korea Toshiyuki Kobayashi, Japan Yanyan Li, United States Nader Masmoudi, United States Haynes R. Miller, United States Nordine Mir, Qatar & France Detlef Müller, Germany Mohamed Sifi, Tunisia Daniel Tataru, United States Sundaram Thangavelu, IndiaSaïd Zarati, Tunisia

Editorial Board

Published in electronic and print formats by mathematical sciences publishers in Berkeley

msp.org/tunisjm

The TJM editorial boardinvites mathematiciansfrom all over the worldto submit high-levelresearch articles.