Editing Phase velocity (section)

===Bibliography===
{{refbegin}}
*Crawford jr.,  Frank S. (1968).  ''Waves (Berkeley Physics Course, Vol. 3)'', McGraw-Hill,  {{ISBN|978-0070048607}} [https://archive.org/details/Waves_371 Free online version]
*{{citation | author-link=Léon Brillouin | last=Brillouin |first=Léon |title=Wave Propagation And Group Velocity |publisher=Academic Press Inc. |location=New York and London |year=1960 |isbn=978-0-12-134968-4 }}
*{{citation |last=Main |first=Iain G. |year=1988 |title=Vibrations and Waves in Physics |edition=2nd |location=New York |publisher=Cambridge University Press |isbn=978-0-521-27846-1 |pages=214–216 }}
*{{citation |last1=Tipler |first1=Paul A. |first2=Ralph A. |last2=Llewellyn |year=2003 |title=Modern Physics |edition=4th |location=New York |publisher=W. H. Freeman and Company |isbn=978-0-7167-4345-3 |pages=222–223 }}
{{refend}}

{{Velocities of Waves}}

{{Authority control}}

[[Category:Wave mechanics]]