The papers in this volume were presented at SWAT 92, the Third Scandinavian Workshop on Algorithm Theory. The workshop, which continues the tradition ofSWAT 88, SWAT 90, and the Workshop on Algorithms and Data Structures (WADS 89, WADS 91), is intended as an international forum for researchers in the area of design and analysis of algorithms. The volume contains invited papers by L.G. Valiant (Direct bulk-synchronous parallel algorithms), A.A. Razborov (On small depth threshold circuits), G. Gonnet (Efficient two-dimensional searching), and E. Welzl (New results on linear programming and related problems), together with 34 selected contributed papers. Contributions cover algorithms and data structures in all areas, including combinatorics, computational geometry, data bases, parallel and distributed computing, and graphics.

This Festschrift was published in honor of Hans L. Bodlaender on the occasion of his 60th birthday. The 14 full and 5 short contributions included in this volume show the many transformative discoveries made by H.L. Bodlaender in the areas of graph algorithms, parameterized complexity, kernelization and combinatorial games. The papers are written by his former Ph.D. students and colleagues as well as by his former Ph.D. advisor, Jan van Leeuwen. Chapter “Crossing Paths with Hans Bodlaender: A Personal View on Cross-Composition for Sparsification Lower Bounds” is available open access under a Creative Commons Attribution 4.0 International License via link.springer.com.

Free radicals, which are key intermediates in many thermal, photochemical and radiation processes, are important for a proper understanding of fundamental natural processes and the successful development of organic syntheses. Volume II/18 serves as a supplement and extension to volume II/13 and covers rate constants and other kinetic data of free radical reactions in liquids. Furthermore II/18 contains new chapters on reactions of radicals in excited states and of carbenes, nitrenes and analogues. Selected species in aqueous solutions for which other compilations are available were deliberately omitted as before, and for the same reason electron transfer equilibria of organic radicals were not covered.

The papers in this volume were presented at SWAT 92, the Third Scandinavian Workshop on Algorithm Theory. The workshop, which continues the tradition ofSWAT 88, SWAT 90, and the Workshop on Algorithms and Data Structures (WADS 89, WADS 91), is intended as an international forum for researchers in the area of design and analysis of algorithms. The volume contains invited papers by L.G. Valiant (Direct bulk-synchronous parallel algorithms), A.A. Razborov (On small depth threshold circuits), G. Gonnet (Efficient two-dimensional searching), and E. Welzl (New results on linear programming and related problems), together with 34 selected contributed papers. Contributions cover algorithms and data structures in all areas, including combinatorics, computational geometry, data bases, parallel and distributed computing, and graphics.