“…First, motivated by dislocation dynamics, we can point out the result done by El Hajj and Boudjerada in [6] wherein the global existence of discontinuous viscosity BV solutions was proved for scalar one dimensional non-linear and non-local eikonal equations, including in particular the case d = 1 in system (1.1). Always within the framework of dislocation dynamics, let us mention that, it was proven in El Hajj et al [9,11,16] some existence and uniqueness results of continuous viscosity solution for a particular quasi-monotone (2 × 2) system which corresponds to the case where (λ i ,j )i,j=1,2 = 1 −1 −1 1 . The proof in [11,16] was based on the work of Ishii, Koike [18,17] wherein, a general theory concerning the existence and the uniqueness of viscosity solutions for quasi-monotone Hamilton-Jacobi systems, has been developed.…”