Citation: Bartalucci, Giuditta; Fisher, Stuart; Helliwell, John R.; Helliwell, Madeleine; Liaaen-Jensen, Synn\/ove; Warren, John E.; Wilkinson, James (2009). X-ray crystal structures of diacetates of 6-s-cis and 6-s-trans astaxanthin and of 7,8-didehydroastaxanthin and 7,8,7',8'-tetradehydroastaxanthin: comparison with free and protein-bound astaxanthins. Acta Crystallographica Section B, 65, pp. 238-247.