It is written by British Masters of Wine Jancis Robinson and Julia Harding in collaboration with Swiss grape geneticist Dr. José Vouillamoz.
Coverage includes a listing of synonyms as well as the genetic relationship between varieties derived from DNA analysis.
After years of research and DNA testing of vines from vineyards across the globe, a single 90-year-old grape vine from the garden of an elderly lady in Split, Croatia provided the evidence to show that Zinfandel was originally a Croatian grape known as Tribidrag that had been cultivated in Croatia since the 15th century.
Additionally the origins of the assumed to be French varieties of Mourvèdre, Grenache and Carignan are shown to likely be Spanish instead.
Traité général de viticulture written by Pierre Viala and Victor Vermorel and published in 1901–1910.