McNeill 2004, p. 32 McNeill, John (2004). "Nomenclature of cultivated plants: a historical botanical standpoint in: C.G. Davidson and P. Trehane (eds), Proc. XXVI IHC – IVth International Symposium on the Taxonomy of Cultivated Plants". Acta Horticulturae. 634 (634): 29–36. doi:10.17660/ActaHortic.2004.634.2.
McNeill 2004, p. 31 McNeill, John (2004). "Nomenclature of cultivated plants: a historical botanical standpoint in: C.G. Davidson and P. Trehane (eds), Proc. XXVI IHC – IVth International Symposium on the Taxonomy of Cultivated Plants". Acta Horticulturae. 634 (634): 29–36. doi:10.17660/ActaHortic.2004.634.2.
McNeill 2004, pp. 25–36 McNeill, John (2004). "Nomenclature of cultivated plants: a historical botanical standpoint in: C.G. Davidson and P. Trehane (eds), Proc. XXVI IHC – IVth International Symposium on the Taxonomy of Cultivated Plants". Acta Horticulturae. 634 (634): 29–36. doi:10.17660/ActaHortic.2004.634.2.
Trehane 2004, pp. 17–27 Trehane, Piers (2004). "50 years of the International Code of Nomenclature for Cultivated Plants: Future prospects for the Code". Acta Horticulturae. 634 (634): 17–27. doi:10.17660/ActaHortic.2004.634.1.