Tombs, M. (2015). European Patent EP1989517: Compensating for frequency change in flowmeters. European Patent Office.
Chicago-viite (17. p.)Tombs, M. European Patent EP1989517: Compensating for Frequency Change in Flowmeters. European Patent Office, 2015.
MLA-viite (9. p.)Tombs, M. European Patent EP1989517: Compensating for Frequency Change in Flowmeters. European Patent Office, 2015.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.