1. From the Pathology, Institute J. Bordet and University of Washington, Seattle, Washington.
2. From the Department of Pathology, University of Arizona, Tucson, Arizona,
3. From the Department of Hospital Brugmann, University of Washington, Seattle, Washington.
4. From the Department of Surgery and'Pathology, Institute J. Bordet,, University of Washington, Seattle, Washington.
5. From the Department of Laboratory of Histology, Free University of Brussels, University of Washington, Seattle, Washington.
6. From the Department of Surgery, Division of Urology, University of Washington, Seattle, Washington.
7. From the Department of Fonds National dela Recherche Scientifique, Brussels, Belgium, University of Washington, Seattle, Washington.