Template:Jacobs et al., 2011
- Jacobs, B., Geuten, K., Pyck, N., Huysmans, S., Jansen, S. & Smets, E. 2011. Unraveling the phylogeny of Heptacodium and Zabelia (Caprifoliaceae): an interdisciplinary approach. Systematic Botany 36(1): 231–252. DOI: 10.1600/036364411X553306