Klimyk, Anatoliy U.; Patera, Jiri
SIGMA, Symmetry Integrability Geom. Methods Appl. 4, Paper 002, 57 p., electronic only (2008)
Roitman, Michael
SIGMA, Symmetry Integrability Geom. Methods Appl. 4, Paper 057, 35 p., electronic only (2008)