MS Bruzón, ML Gandarias, C Muriel, J Ramírez, S Saez and FR Romero (pdf copy 300 Kb)
We use the classical and nonclassical methods to obtain symmetry reductions and exact solutions of the (2+1)-dimensional integrable Calogero–Bogoyavlenskii–Schiff equation. Although this (2+1)-dimensional equation arises in a nonlocal form, it can be written as a system of differential equations and, in potential form, as a fourth-order partial differential equation. The classical and nonclassical methods yield some exact solutions of the (2+1)-dimensional equation that involve several arbitrary functions and hence exhibit a rich variety of qualitative behavior.
Theoretical and Mathematical Physics 137(1): 1367-1377, October, 2003, doi:10.1023/A:1026040319977