The encyclopedia of the plant kingdom - Huxley, Anthony; Bladon, Hilary; Chapman, J. M.; Crisp, Peter; Gibson, D. P.; Giles, Barry; Edlin, Herbert L.; Grimes, Hannah; Grimes, J. W.; Horton, Philip; Mason, John; Paterson, Allen; et al. (The Hamlyn Publishing Group Limited, 1977)