RT Journal Article SR Electronic T1 Letters JF The Journal of the Royal College of General Practitioners JO J R Coll Gen Pract FD British Journal of General Practice SP 368 OP 368 VO 37 IS 301 A1 Tony Waterston A1 T. Van Zwanenberg YR 1987 UL http://bjgp.org/content/37/301/368.4.abstract AB