N. L. Britton, J. N. Rose: The Cactaceae. Descriptions and Illustrations of Plants of the Cactus Family. BandIV. The Carnegie Institution of Washington, Washington 1923, S.138 (online).
doi.org
Peter B. Breslin, Martin F. Wojciechowski, Lucas C. Majure: Molecular phylogeny of the Mammilloid clade (Cactaceae) resolves the monophyly of Mammillaria. In: Taxon. Band 70, Nr. 2, 2021, S. 318 (doi:10.1002/tax.12451).