INTERNATIONAL CODE OF NOMENCLATURE FOR CULTIVATED PLANTS: APPENDIX III
APPENDIX IV

APPENDIX III: Special denomination classes (those taxonomic units in which cultivar names may not be duplicated and which are not a single genus)

APPENDIX IV: Places maintaining nomenclatural standards (herbaria of the world which have a policy of holding and actively maintaining specimens of cultivars, including contact information).

International Code of Nomenclature for Cultivated Plants – Code International pour la Nomenclature des Plantes Cultivees

C.D. Brickell, B.R. Baum, W.L.A. Hetterscheid, A.C. Leslie, J. McNeill, P. Trehane, F. Vrugtman, J.H. Wiersema

https://doi.org/10.17660/ActaHortic.2004.647.12