Analysis of protective immunity against PRV infection in pigs using attenuated and inactivated PRV vaccines E.M.A. van Rooij, M.G.M. de Bruin, Y.E. de Visser, W. Boersma and A.T.J. Bianchi Vet. Res., 31 1 (2000) 135 DOI: 10.1051/vetres:2000063