Vertical Human Immunodeficiency Virus Transmission: A Study of Placental Pathology in Relation to Maternal Risk Factors - Backé, Eva; Jimenez, Etha; Unger, Matthias; Schäfer, Axel; Vocks-Hauck, Mechthild; Grosch-Wörner, Ilse; Vogel, Martin (American Journal of Perinatology, 1994)