Distinction between infections with European and American/vaccine type PRRS virus after vaccination with a modified-live PRRS virus vaccine A. Bøtner, B. Strandbygaard, K. J. Sørensen, M. B. Oleksiewicz and T. StorgaardVet. Res., 31 1 (2000) 72DOI: https://doi.org/10.1051/vetres:2000009