Efficacy of an American and a European serotype PRRSV vaccine after challenge with American and European wild–type strains of the virus G. G. Labarque, H. J. Nauwynck, P. A.M. van Woensel, N. Visser and M. B. PensaertVet. Res., 31 1 (2000) 97DOI: https://doi.org/10.1051/vetres:2000026