6Yoon K J, Wu L L, Zimmerman J J ,et al. A modified serum neutralization test for the detection of antibody to porcine reproductive and vespiratory syndrome virus in swine sera[J].Vet Diagn Invest,1994,6(2):289-292.
7Keffaber K K. Reproductive failuer of unknown etiology[J].Am Assoc Swine Pract News, 1989,1(1):1-9.
8Wensvoort G, Terpstra C. Mystery swine disease in the Netherland: the isolation of lelystad virus[J].J Vet Q,1991,13:121-130.
9Collins J E, Benfield D A, Christianson W T, et al. Isolation of swine infertility and experimental reproduction of the disease in gnotobiotic pigs[J]. J Vet Diagn Invest,1992,4:117-126.
10Yoon I J, Joo H S, Chrisrianson W T. An indirect fluorescent antibody test for the detection of antibody to swine infertility and respiratory syndrome virus in swine sera[J].J Vet Diagn Invest,1992,4:144-147.