| Identifier | Reference | 
| [CSDGM] | 
 Federal Geographic Data Committee.
 FGDC-STD-001-1998.
 Content standard for digital geospatial metadata (revised June 1998).
 Federal Geographic Data Committee. Washington, D.C.
 | 
| [FOLEY_VAN_DAM] | 
 Foley, van Dam, et. al, Computer Graphics: Principles and Practice,
 2nd edition. Addison-Wesley, 1992.
 | 
| [I18026] | 
 ISO/IEC WD5 18026:200x Information technology - Computer graphics
 and image processing - Spatial reference model (SRM).
 
 http://www.iso.org
 | 
| [OPENGL] | 
 OpenGL Architecture Review Board. OpenGL Programming Guide,
 3rd edition. Addison-Wesley, 1999.
 |