RT Journal Article SR Electronic T1 The Measurement of Peak Expiratory Flow Rate and its Application in General Practice JF The Journal of the College of General Practitioners JO J Coll Gen Pract FD British Journal of General Practice SP 199 OP 214 VO 7 IS 2 A1 Ian Gregg YR 1964 UL http://bjgp.org/content/7/2/199.abstract AB