Antiproliferative Amaryllidaceae Alkaloids Isolated from the Bulbs of Sprekelia formosissima and Hymenocallis × festalis - Hohmann, Judit; Forgo, Peter; Molnár, Joseph; Wolfard, Krisztina; Molnár, Annamária; Thalhammer, Theresia; Máthé, Imre; Sharples, Derek (Planta Medica, 2002)