 | B. Mashhon , University of Missouri-Columbia, Columbia, USA,
Sep. 1 - Oct. 1, 1991 |
| H. Woodin , University of California, Berkeley, Berkeley, USA,
Aug. 1 - Sep. 1, 1991 |
 | K. Hauser , University of California, Berkeley, Berkeley, USA,
Aug. 1 - Sep. 1, 1991 |
| J. Larson , University of Florida, Gainesville, USA,
Aug. 1 - Sep. 1, 1991 |
| R. Laver , University of Colorado, Boulder, USA,
Aug. 1 - Sep. 1, 1991 |
| W. Mitchell , University of Florida, Gainesville, USA,
Aug. 1 - Sep. 1, 1991 |
| M.A. Shokrollahi , Informatics Institute, Bonn, Germany,
Dec. 1, 1990 - Jan. 1, 1991 |
| S. Shokranian , University of Brasilia, Brasilia, Brazil,
Dec. 1, 1990 - Jan. 1, 1991 |
| A.H. Assadi , University of Wisconsin-Madison, Wisconsin, USA,
March 1, 1990 - June 1, 1991 |
|
