%0 Book Section %T Lie algebras obtained as extensions by derivations of the nilpotent algebra L5,3 publisher Universidad Complutense de Madrid %D 2012 %U 978-84-695-4421-1 %@ https://hdl.handle.net/20.500.14352/45356 %X For the only quasi-filiform Lie algebra L5,3 admitting a Levi factor in its Lie algebra of derivations, the extensions by derivations are classified over C and R. Moreover, the invariants of these extensions are computed. %~