1. Department of Biology, Duke University, Durham, North Carolina 27708-0338
2. Institut für Botanik, Karl-Franzens-Universität, Holteigasse 6, A-8010, Graz, Austria
3. Department of Plant Taxonomy and Nature Conservation, Gdansk University, A. Legionow 9, 80-441 Gdansk, Poland
4. Field Museum of Natural History, 1400 South Lake Shore Drive, Chicago, Illinois 60605-2496
5. Department of Biology, University of Oslo, P.O. Box 1066 Blindern, NO-0316 Oslo, Norway
6. Área de Biodiversidad y Conservación, ESCET, Universidad Rey Juan Carlos, c/ Tulipán s/n, 28933-Móstoles, Madrid, Spain
7. Fachbereich Biologie, Abt. Pflanzenökologie und Systematik, University of Kaiserslautern, Postfach 3049, 67653 Kaiserslautern, Germany
8. Swiss Federal Institute for Forest, Snow and Landscape Research (WSL/FNP), Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
9. Botanical Museum, University of Oslo, Sars’ gate 1, N-1162 Oslo, Norway
10. Botanical Museum, Finnish Museum of Natural History, University of Helsinki, P.O. Box 7, FI-00014 Finland
11. Canadian Museum of Nature, P.O. Box 3443, Station D, Ottawa, Ontario, K1P 6P4 Canada
12. North Carolina Botanical Garden, University of North Carolina at Chapel Hill, CB 3375, Totten Center, Chapel Hill, North Carolina 27599-3375
13. National Botanic Garden of Belgium, Department of Bryophytes-Thallophytes, Domaine de Bouchout, B-1860 Meise, Belgium
14. Musée national d’histoire naturelle, 25 rue Munster, L-2160 Luxembourg, Luxembourg
15. Department of Botany, Academy of Natural Sciences of Philadelphia, 1900 Benjamin Franklin Parkway, Philadelphia, Pennsylvania 19103
16. Farlow Herbarium, Harvard University, 22 Divinity Avenue, Cambridge, Massachusetts 02138
17. Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon
18. Department of Plant Sciences, University of Arizona, 1140 E. South Campus Drive, Forbes 204, Tucson, Arizona 85721