- 1983[subject unknown]Independent
- 1989[subject unknown]Independent
- 1996[subject unknown]Principal Investigators
- 1997[subject unknown]Principal Investigators
- 1998[subject unknown]Principal Investigators
- 1999[subject unknown]Principal Investigators
- 2000[subject unknown]Principal Investigators
- 2001[subject unknown]Principal Investigators
- 2002[subject unknown]Summer Investigators