Origin of British x-ray film sizes.
D049670:History, 17th Century; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D010781:Photography / Q000266:history; D013679:Technology, Radiologic / Q000266:history*; D006113:United Kingdom; D014894:Weights and Measures / Q000266:history*