Heterologous vaccine immunogenicity, efficacy, and immune correlates of protection of a modified-live virus porcine reproductive and respiratory syndrome virus vaccine oleh Jessica Proctor, Iman Wolf, David Brodsky, Lizette M. Cortes, Alba Frias-De-Diego, Glen W. Almond, Elisa Crisci, Tatiane Terumi Negrão Watanabe, James M. Hammer, Tobias Käser