... Johnson¹

Published in ACM SIGACT News, December 1998.

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... \author²

Dipartimento di Sistemi ed Informatica, Università di Firenze, Via Cesare Lombroso 6/17, 50134 Firenze, Italy, piluc@dsi.unifi.it

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... \author³

Department of Numerical Analysis and Computing Science, Royal Institute of Technology, SE-100 44 Stockholm, Sweden, viggo@nada.kth.se
Copyright © Pierluigi Crescenzi and Viggo Kann, 1998

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