Safety and immunogenicity of the 23-valent pneumococcal polysaccharide vaccine at 12 months of age, following one, two, or three doses of the 7-valent pneumococcal conjugate vaccine in infancy.
Russell FM, Licciardi PV, Balloch A, Biaukula V, Tikoduadua L, Carapetis JR, Nelson J, Jenney AW, Waqatakirewa L, Colquhoun S, et al. Vaccine. 2010 Apr 19; 28(18):3086-94. Epub 2010 Mar 1.