Marbach, J R An empirical table of equivalent squares of rectangular fields for the Theratron 780. [electronic resource] - The British journal of radiology May 1977 - 360-2 p. digital Publication Type: Journal Article ISSN: 0007-1285 Standard No.: 10.1259/0007-1285-50-593-360 doi Subjects--Topical Terms: Cobalt RadioisotopesRadioisotope Teletherapy--standards