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2. Future influenza vaccines and the use of genetic recombinants;Kilbourne;Bull World Health Organisation,1969
3. Recommended composition of influenza virus vaccines for use in the 1991–1992 season;WHO;Wkly Epidem Rec,1991
4. Recommended composition of influenza virus vaccines for use in the 1992–1993 season;WHO;Wkly Epidem Rec,1992
5. Influenza virus neuraminidase and neuraminidase-inhibition test procedures;Aymard-Henry;Bull World Health Organisation,1973