1. Bugawan, T. L., Horn, G. T., Long, C. M., Mickelson, E., Hansen, J. A., Ferrara, G. B., Angelini, G., and Erlich, H. A.: Analysis of HLA-DP allelic sequence polymorphism using the in vitro enzymatic DNA amplification of DPα and DPβ loci.J Immunol 141: 4024–4030, 1988