LETTERS. - Robinson, Ray; New, Bill; Tomlin, P.J.; Bignell, C.J.; Lems, W.F.; Bijlsma, J.W.J.; Kontula, Kimmo; Chung, K.F.; Wells, A.; Stamp, T.; Homer, Ann; Haddad, P.M.; et al. (BMJ: British Medical Journal (International Edition), 1992)