This volume is dedicated to A.C. Zaanen, one of the pioneers of functional analysis, and eminent expert in modern integration theory and the theory of vector lattices, on the occasion of his 80th birthday. The book opens with biographical notes, including Zaanen's curriculum vitae and list of publications. It contains a selection of original research papers which cover a broad spectrum of topics about operators and semigroups of operators on Banach lattices, analysis in function spaces and integration theory. Special attention is paid to the spectral theory of operators on Banach lattices; in particular, to the one of positive operators. Classes of integral operators arising in systems theory, optimization and best approximation problems, and evolution equations are also discussed. The book will appeal to a wide range of readers engaged in pure and applied mathematics.

Inhalt
Biographical notes.- List of Publications of A.C. Zaanen.- Curriculum Vitae of A.C. Zaanen.- Another characterization of the invariant subspace problem.- Matrix Young inequalities.- Principal eigenvalues and perturbation.- Input-output operators of J-unitary time-varying continuous time systems.- Optimization without compactness, and its applications.- On a submajorization inequality of T. Ando.- Spectral theory on Banach lattices.- Disjointness preserving operators on Banach lattices.- The Daniell-Stone-Riesz representation theorem.- Diagonals of the powers of an operator on a Banach lattice.- A characterization of Lipschitz continuous evolution families on Banach spaces.- On the Vitali-Hahn-Saks theorem.- Minkowski's integral inequality for function norms.- Program of the 1993 Zaanen Symposium.