The general addition theorem and ladder operators. - Jesús García-Ravelo; Alfonso Queijeiro; Rogelio Cuevas; J. J. Peña; J. Morales (Appl. Math. Lett., 2007)

Two-parameter ladder operators for spherical Bessel functions. - Jesús García-Ravelo; Axel Schulze-Halberg; José Juan Peña Gil; Alfonso Queijeiro (Appl. Math. Lett., 2010)