Calvente A., Zappi D. C., Forest F., Lohmann L. G., Molecular phylogeny of tribe Rhipsalideae (Cactaceae) and taxonomic implications for Schlumbergera and Hatiora, Molecular Phylogenetics and Evolution, 2011, 58(3):456-468, doi: 10.1016/j.ympev.2011.01.001
Analysis of three plastid markers and nuclear ITS in 35 Rhipsalideae species, combined with morphological character assessment. The authors evaluated major relationships, historical genus boundaries and the evolution of stems and flowers. They proposed a broader Schlumbergera containing the former Hatiora subg. Rhipsalidopsis.