Tombs, M. (2015). European Patent EP1989517: Compensating for frequency change in flowmeters. European Patent Office.
芝加哥风格引文Tombs, M. European Patent EP1989517: Compensating for Frequency Change in Flowmeters. European Patent Office, 2015.
MLA引文Tombs, M. European Patent EP1989517: Compensating for Frequency Change in Flowmeters. European Patent Office, 2015.
警告：这些引文格式不一定是100％准确.