Conference on Semigroups (1981 : Oberwolfach, Germany). Recent developments in the algebraic, analytical, and topological theory of semigroups, 1983 CIP t.p. (K.H. Hofmann) verso t.p. (Fachbereich Mathematik, Technische Hochschule Darmstadt, Fed. Rep. Germany) data sheet (b. 10/3/32)
Semigroups in algebra, geometry, and analysis, 1995 CIP t.p. (Karl H. Hofmann)
Crimes and mathdemeanors, 2007 ECIP t.p. (Karl Hofmann, illustrator)