1. Fortran 90 Standard ISO/IEC 1539:1991
2. Fortran 96 Standard, ISO/IEC 1539:1996
3. Varying Length Character Strings in Fortran, ISO/IEC 1539-2:1994.
4. High Performance Fortran Language Specification, HPFF, Version 1.1, November 1994.
5. Adobe Systems Incorporated, Postscript Language: Tutorial and Cookbook, Addison Wesley, 1985.