1. GOST R 8.583–2001 (IEC 61689–96), GSI. Medical Ultrasonic Therapeutic Equipment. General Requirements for Techniques of Performing Measurements of the Parameters of Acoustic Yield in the Frequency Range from 0.5 to 5.0 MHz.
2. GOST R MEK 61157–2008, GSI. Electrical Medical Articles. Devices for Ultrasonic Diagnostics. Requirements for the Representation of the Parameters of Acoustic Yield in Technical Documentation.
3. K. Beissner, “Report on key comparison CCAUV.U-K1 (ultrasonic power),” Metrologia, No. 39 (2002), Tech. Suppl. 09001.
4. C. Koch and K.-V. Jenderka, “Report on key comparison CCAUV.U-K3 for ultrasonic power,” Metrologia, 51 (2014), Tech. Suppl. 09001.
5. BIPM, http://www.bipm.org/ , accessed 03.07.2014.