1. Dale R Patrick & Stephen W Fando,Industrial ProcessControl Systems, Prentice Hall Inc, pp 109–129, 1983.
2. B E Noltingk,Instrumentation Reference Book, Butterworth-Heinemann Ltd, 2nd ed, Part-1, pp 1–39, 1995.
3. John P Bentley,Principles of Measurement Systems, Longman Group Limited, UK, 2nd ed, pp 331–337, 1988.
4. Flow sensors based on surface acoustic waves