TIFF Revision 5.0 (”In fact, the TIFF version number (42) has never changed, and probably never will. If it ever does, it means that TIFF has changed in some way so radical that a TIFF reader should give up immediately. The number 42 was chosen for its deep philosophical significance.”) Aldus/Microsoft. Viitattu 6.9.2008. (englanniksi)