R. E. Behrends^*, J. Dreitlein^†, C. Fronsdal^‡, and W. Lee^§

• University of Pennsylvania, Philadelphia, Pennsylvania

• ^*Now at the Graduate School of Science, Yeshiva University, New York.
• ^†National Science Foundation Postdoctoral Fellow 1960-1961. Now at Stanford University, Stanford, California.
• ^‡On leave of absence from the University of Bergen, Norway. Now at University of California, Los Angeles, California.
• ^§Now on leave of absence at the Institute for Advanced Study, Princeton, New Jersey.