“Minimal Matrix Representations of Decomposable Lie Algebras of Dimension Less Than or Equal to Five: Doi:10.17398 2605-5686.33.2.219”. Extracta Mathematicae, vol. 33, no. 2, Dec. 2018, p. 219-27, https://revista-em.unex.es/index.php/EM/article/view/2605-5686.33.2.219.