British Medical Journal, 1897, v.2, pp. 904
Hill and Barnard made an important modification to the Rive-Rocci sphygmomanometer when they substitued a pressure guage in place of the mercury manometer used for pressure readings.
Morton no.: 2807
Hill, Sir Leonard Erskine and Barnard, Harold Leslie, "A simple and accurate form of sphygmomanometer or arterial pressure gauge contrived for clinical use." (1897). Classic Article Collection. 100.