1 | Institut de Botanique, Université de Liège, Liège, Belgium |
2 | Meise Botanic Garden, Meise, Belgium |
3 | Department of Ecology and Evolutionary Biology, University
of Connecticut, Storrs CT, USA |
4 | Musée national d’histoire naturelle, Luxembourg, Luxembourg |
5 | W. Szafer Institute of Botany, Polish Academy of Sciences,
Kraków, Poland |
6 | Department of Biology, Duke University, Durham NC, USA |