2010BS ISO 5-1:2010 Photography and graphic technology. Density measurements Geometry and functional notation
2010BS ISO 5-1:2009 Photography and graphic technology - Density measurements - Geometry and functional notation
1985BS 1384-1:1985 Photographic density measurements - Guide for terms, symbols and notations
BS ISO 5-1:2009 Photography and graphic technology - Density measurements - Geometry and functional notation has been changed from BS 1384-1:1985 Photographic density measurements - Guide for terms, symbols and notations.