UNSPECIFIED – CIRCA 1997: Pierre Viala (1859-1936), Victor Vermorel (1848-1927), Traite General de Viticulture. Ampelographie, 1901-1910. Tome II, plate: Chenin Blanc grape. Illustration by J. Troncy. (Photo By DEA / A. DAGLI ORTI/De Agostini via Getty Images)
