Jens Treutlein, Gideon F. Smith, Ben-Erik Van Wyk, M. Wink: Evidence for the Polyphyly of Haworthia (Asphodelaceae Subfamily Alooideae; Asparagales) Inferred from Nucleotide Sequences of rbcL, matK, ITS1 and Genomic Fingerprinting with ISSR-PCR. In: Plant Biology. Band 5, Nummer 5, 2003, S. 520 (doi:10.1055/s-2003-44793).
J. C. Manning, J. S .Boatwright, B. H Daru, O. Maurin, M. van der Bank: A molecular phylogeny and generic classification of Asphodelaceae subfamily Alooideae: A final resolution of the prickly issue of polyphyly in the Alooids. In: Systematic Botany. Band 39, Nr. 1, 2014, S. 55–74 (doi:10.1600/036364414X678044).
haworthia.org
haworthia-updates.haworthia.org
H. A. Duval: Plantae succulentae in horto Alenconio. Gabon et Cie, Paris 1809, S. 7 (Reprint).
alsterworthia.haworthia.org
S. Ramdhani, M. B. Bayer, R. M. Cowling, N. P. Barker: Molecular phylogenetic studies in Haworthia Duval (Asphodelaceae). In: Alsterworthia International. The Succulent Asphodelaceae Journal. Band 9, Nr. 3, 2009, S. 13–17 (PDF).
jstor.org
S. Ramdhani, N. P. Barker, R. M. Cowling: Revisiting monophyly in Haworthia Duval (Asphodelaceae): Incongruence, hybridization and contemporary speciation. In: Taxon. Band 60, Nr. 4, 2011, S. 1001–1014 (JSTOR:41317322).
B. H. Daru, J. C. Manning, J. S. Boatwright, O. Maurin, N. Mclean, H. Schaefer, M. Kuzmina, M. van der Bank: Molecular and morphological analysis of subfamily Alooideae (Asphodelaceae) and the inclusion of Chortolirion in Aloe. In: Taxon. Band 62, Nr. 1, 2013, S. 62–76 (JSTOR:24389313).