RT Journal Article SR Electronic(1) A1 R Harling YR 2003 T1 Further information in support of a selective smallpox vaccination policy JF Weekly releases (1997–2007) VO 7 IS 1 SP 1994 OP DO https://doi.org/10.2807/esw.07.01.01994-en UL https://www.eurosurveillance.org/content/10.2807/esw.07.01.01994-en