Europium(III) and terbium(III) `beta´-diketonate adducts with 2,6-dimethylmorpholine: synthesis, characterization and emission spectra - Trikha, A. K.; Kaur, S.; Rittner, R.; Zinner, Lea Barbieri; Zinner, Klaus; Isolani, Paulo Celso; Vicentini, Geraldo (Journal of Coordination Chemistry, 1999)