# April 1972 - Vol. 15 No. 4

## Features

On the implementation of security measures in information systems

A system for interprocess communication in a resource sharing computer network

An experimental laboratory for pattern recognition and signal processing

Hidden lines elimination for a rotating object

An implemented graph algorithm for winning Shannon Switching Games

Computers and society: a proposed course for computer scientists

Complex gamma function with error control

Matrix computations with Fortran and paging

Algorithm 421: complex gamma function with error control [S14]

Algorithm 422: minimal spanning tree [H]

A note on Cheney’s nonrecursive list-compacting algorithm

A comment on the double-chained tree