1. EMWorks Inc., Lasalle, QC, Canada H8N 2X2
2. Department of Mathematics, Swansea University, Singleton Park, Swansea SA2 8PP, UK
3. Polytechnic Department of Engineering and Architecture (DPIA), Università di Udine, 33100 Udine, Italy
4. Ecole de Technologie Superieure, Montreal, QC, Canada H3C 1K3