1. Park, W. W. (1985). Possible functions of non-villous trophoblast. In Brosens, I., Dixon, G. and Robertson, W. (eds.) Human Placentation. pp.33–46. ( Amsterdam: Excerpta Medica )
2. Sutherland, C. A., Redman, C. W. and Stirrat, G. M. (1981). HLA A, B, C antigens are expressed on non-villous trophoblasts of the early human placenta. J. Immunol., 127,2614–15
3. Bulmer, J. N. and Johnston, P. M. (1985). Antigen expression by trophoblast populations on the human placenta and their possible immunological relevance. Placenta, 6, 127–40
4. Mclntyre, J. A. and Faulk, W.P. (1986). Trophoblast antigens in normal and abnormal human pregnancy. Clin. Obstet. Gynecol., 29, 976–98
5. Peer, L. A. (1958). Behaviour of skin grafts exchanged between parents and offspring. Ann. NY Acad. Sci., 73, 584–9