The aim of this paper is to study some brackets defined on
(τ,σ)-derivations satisfying quasi-Lie identities. Moreover, we
provide examples of (p,q)-deformations of Witt and Virasoro algebras as well
as sl(2) algebra. These constructions generalize the results
obtained by Hartwig, Larsson and Silvestrov on σ-derivations, arising in
connection with discretizations and deformations of algebras of vector fields.Comment: 30 page