AUTHOR : Torrisi M.

 

1.ааа Differential Invariants for a Class of Nonlinear Wave Equations

M.Torrisi, A.Valenti (Dipartimento di Matematica e Informatica, University of Catania, Catania, Italy); N.H.Ibragimov (Research Centre ALGA: Advances in Lie Group Analysis, Department of Health, Science and Mathematics, Blekinge Institute of Technology, Karlskrona, Sweden)

2.ааа On Certain Equivalence Transformations

M.Torrisi (Department of Mathematics and Informatics, University of Catania, Catania, Italy)