RT Journal Article SR Electronic T1 VACCINATION CERTIFICATE REQUIREMENTS FOR INTERNATIONAL TRAVEL AND HEALTH ADVICE TO TRAVELLERS JF The Journal of the Royal College of General Practitioners JO J R Coll Gen Pract FD British Journal of General Practice SP 114 OP 114 VO 32 IS 235 A1 S. L. Barley YR 1982 UL http://bjgp.org/content/32/235/114.1.abstract AB