I bumped in to an excellent article 'Deriving Projection Matrices' posted by Joe Farrell on July 11th, 2005. This is he URL of this.

Somhow, i am not able to see the gif images on page2 and page3of this artcile.

Can anybody please let Joe Farrel know about this so that it can be corrected ? or may be the moderator can correct this.

I am really in need of this wonderful artcile and i really appreciate this getting corrected.