The French ampelographer Paul Truel (1924-2014) is considered one of the world's leading experts in this field. He studied at the Department of Viticulture at the French University in Montpellier (Languedoc). This was at the time when Pierre Galet (1921-2019) was head of the viticulture department there. Like Galet, he was an absolute specialist in the identification of grape varieties, which he could often identify spontaneously and purely visually on the basis of the phenotype. For many years, Paul Truel was in charge of the INRA (now INRAE) grape variety collection at the Domaine de Vassal.