FOCUS (Computer program language)

Guide to advanced FOCUS programming

Joseph DeVita, Frank Paino.

The illustrated PC/FOCUS book

Bart L. Benne.

FOCUS developer's handbook

Bart Benne.

An end-users guide to FOCUS

Ian A. Davies.

FOCUS keysheet: quick reference guide

John W. Price.

PC/FOCUS: breaking through the barriers : version 1

written by Steve Dorr.

PC/FOCUS, version 5.5: a step-by-step tutorial

Morris Nassi, Samia Assaad.

Focus made easy: the complete Focus handbook for users and programmers

Richard R. Taha.

Working with FOCUS: an introduction to database management

Clifford A. Schaffer.

The database experts' guide to FOCUS

Joseph DeVita.