MEJLBO, Lars C. On the Solution of the Commutation Relation $PQ - QP = -iI$. Mathematica Scandinavica, Berkeley, CA, United States, v. 13, p. 129–139, 1963. DOI: 10.7146/math.scand.a-10695. Disponível em: https://journals.msp.org/mscand/article/view/2630. Acesso em: 25 jul. 2026.