Burge D. O., Mugford K., Hastings A. P., Agrawal A. A., Phylogeny of the plant genus Pachypodium (Apocynaceae), PeerJ, 2013, 1:e70, doi: 10.7717/peerj.70
An ITS and chloroplast trnL-F phylogeny includes 56 samples representing 21 species and 27 minimum-rank taxa in the classification used. Relationships among major African and Malagasy lineages remained poorly resolved.