Communications of the ACM

A letter from the ACM president: whither our chapters?

W. M. Carlson
Pages 219-220

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Program development by stepwise refinement

Niklaus Wirth
Pages 221-227

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Key-to-address transform techniques: a fundamental performance study on large existing formatted files

V. Y. Lum, P. S. T. Yuen, M. Dodd
Pages 228-239

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Dynamic microprogramming: processor organization and programming

Allen B. Tucker, Michael J. Flynn
Pages 240-250

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Animator: an on-line two-dimensional film animation system

Peggy Anne Talbot, John W. Carr, Richard R. Coulter, Rosa C. Hwang
Pages 251-259

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On complement division

Marvin L. Stein
Pages 260-264

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Algorithm 408: a sparse matrix package (part I) [F4]

John Michael McNamee
Pages 265-273

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Software and patents: a status report

Elmer W. Galbi
Pages 274-280

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Patents and programs: the ACM's position

Michael A. Duggan
Pages 278-279

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