(2) ISO 9300:2004, Measurement of gas flow by means of critical flow Venturi nozzles (2004), ISO.
(3) 中尾晨一, “70 MPa充てん機用音速ノズル式流量計の開発とその評価試験”, FC Academic Forum, FC EXPO 2006 (2006-3).
(4) Nakao, S., “Development of the critical nozzle flow meter for high pressure hydrogen gas dispenser at a hydrogen gas station”, FLOMEKO 2005 (2005-6).