This volume is published on the occasion of Gunter Hotz's sixtieth birthday. It contains works by his students, friends, and colleagues. Gunter Hotz has been a professor of Numerical Mathematics and Computer Science at the University of Saarland since 1969. He has played a significant role in the establishment of the Computer Science department at the University of Saarland and has greatly influenced the development of computer science in Germany. This is impressively demonstrated by the diversity of the works presented here. With the contributions in this book, the authors wish to express a part of their gratitude to Mr. Hotz, to whom they feel indebted for various reasons. Saarbrücken, November 1991 J. Buchmann, H. Ganzinger, W. J. Paul Table of Contents Abolhassan, Drefenstedt, Keller, Paul, Scheerer: On the Physical Design of PRAMs.