1. Diseases of the umbilical cord;deSa DJ, I.,1984
2. Seltsame veraderungen an den Nabelschnurgefassen;Rust, W.;Arch Gynak,1937
3. Uber das odem der Nabelschnur;Walz, W.;Zentralbl Gynak,1947
4. Degeneration and calcification of the umbilical cord;Perrin, E.V.D.; Kahn-Vander Bel, J.;Obstet Gynecol,1965
5. Pathology ofthe umbilical cord and fetal membranes;Kohler, H.G.,1987