Communications of the ACM

On the proof of correctness of a calendar program

Leslie Lamport
Pages 554-556

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Line numbers made cheap

Paul Klint
Pages 557-559

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An algorithm for planning collision-free paths among polyhedral obstacles

Tomás Lozano-Pérez, Michael A. Wesley
Pages 560-570

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ACM forum

Robert L. Ashenhurst
Pages 577-579

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Comment on “an optimal evaluation of Boolean expressions in an online query system”

P. D. Laird
Pages 549-553

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