https://holidayrecipestocook.com/2021/03/17/arthur-stoll-and-albert-hofmann-partial-synthesis-of-alkaloids-of-the-ergobasin-type-helvetica-chemica-acta-1943-volume-26-page-944-965/
Arthur Stoll, and Albert Hofmann, “Partial Synthesis of Alkaloids of the Ergobasin Type”, Helvetica Chemica Acta, 1943, volume 26, page 944-965.