Álvarez, E., A. Fernández-García, C. Prieto, J. Martínez-Lobo, I. Simarro, and J. M. Castro. 2006. “Efficacy of a Spanish Modified Live Virus Vaccine Against Homologous Porcine Reproductive and Respiratory Syndrome Virus Infection”. Spanish Journal of Agricultural Research 4 (3), 213-20. https://doi.org/10.5424/sjar/2006043-6299.