1. The c programming language;Kernighan,1978
2. Johnson, AG, Statham, E and Doyle, JRWriting faster c available from Real Time Systems, Elliott Terrace, Newcastle on Tyne, NE4 6UP, UK
3. Bell Laboratories, Murray Hill, NJ, USA
4. Whitesmiths Ltd, 97 Lowell Road, Concord, MA, USA
5. Two programs, many Unix systems;Tannenbaum;EUUG Newsletter,1983