Template:Groeninckx et al., 2009
- Groeninckx, I., Dessein, S., Ochoterena, H., Persson, C., Motley, T.J., Kårehed, J., Bremer, B., Huysmans, S. & Smets, E. 2009. Phylogeny of the Herbaceous Tribe Spermacoceae (Rubiaceae) Based on Plastid DNA Data1. Annals of the Missouri Botanical Garden 96(1): 109–133. DOI: 10.3417/2006201
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