document: ITIS & Species 2000 Catalogue of Life Management Hierarchy; M. Ruggiero & D. Gordon, eds. 2011. Consensus Management Hierarchy for the ITIS & Species2000 Catalogue of Life. Contributors: Nicolas Bailly, Thierry Bourgoin, Richard Brusca, Thomas Cavalier-Smith, Daphne Fautin, Dennis Gordon, Gerald Guala, Michael Guiry, Paul Kirk, Elliot Lefkowitz, David Mabberly, David Maddison, Alan Paton, Michael Ruggiero, Peter Stevens, and Brian Tyndall
database: NODC Taxonomic Code;
database: The PLANTS Database; National Plant Data Center, NRCS, USDA. Baton Rouge, LA 70874-4490 USA. http://plants.usda.gov
database: The PLANTS Database; National Plant Data Center, NRCS, USDA. Baton Rouge, LA 70874-4490 USA. http://plants.usda.gov
Christenhusz, Maarten J. M., Xian-Chun Zhang, and Harald Schneider 2011-02-18. Phytotaxa, vol. 19. . . 7-54. . Available online at http://www.mapress.com/phytotaxa/content/2011/f/pt00019p054.pdf.
