1. Laboratories of Experimental Hematology, The Children’s Cancer Research Foundation, and the Department of Pathology, Harvard Medical School at The Children’s Hospital, Boston, Mass.
2. The Children's Cancer Research Foundation and the Departments of Pathology, The Children's Ho,spital Medical Center and Harvard Medical School, Boston, Mass.
3. The Children's Cancer Research Foundation and the Department of Pathology, The Children's Hospital Medical Center, Boston, Mass.
4. The Children's Cancer Research Foundation and the Department of Pathology, The Children's Hospital Methcal Center, Boston, Mass.