Editing Group velocity (section)

===Further reading===

{{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
| 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
| postscript = .
| page=223
}}
* {{Citation
| doi = 10.1103/PhysRev.105.1129
| volume = 105
| issue = 4
| pages = 1129–1137
| last = Biot
| first = M. A.
| title = General theorems on the equivalence of group velocity and energy transport
| journal = Physical Review
| year = 1957
|bibcode = 1957PhRv..105.1129B }}
* {{Citation
| doi = 10.1002/cpa.3160140337
| volume = 14
| issue = 3
| pages = 675–691
| last = Whitham
| first = G. B.
| title = Group velocity and energy propagation for three-dimensional waves
| journal = Communications on Pure and Applied Mathematics
| year = 1961
| citeseerx = 10.1.1.205.7999
}}
* {{Citation
| doi = 10.1093/imamat/1.1.1
| volume = 1
| issue = 1
| pages = 1–28
| last = Lighthill
| first = M. J.
| title = Group velocity
| journal = IMA Journal of Applied Mathematics
| year = 1965
}}
* {{Citation
| doi = 10.1098/rspa.1968.0034
| volume = 302
| issue = 1471
| pages = 529–554
| last1 = Bretherton
| first1 = F. P.
| author1-link = Francis Patton Bretherton
| first2 = C. J. R.
| last2 = Garrett
| title = Wavetrains in inhomogeneous moving media
| journal = Proceedings of the Royal Society of London
| series =Series A, Mathematical and Physical Sciences
| year = 1968
|bibcode = 1968RSPSA.302..529B | s2cid = 202575349
}}
* {{Citation
| doi = 10.1098/rspa.1973.0021
| volume = 332
| issue = 1589
| pages = 199–221
| last = Hayes
| first = W. D.
| title = Group velocity and nonlinear dispersive wave propagation
| journal = Proceedings of the Royal Society of London
| series = Series A, Mathematical and Physical Sciences
| year = 1973
|bibcode = 1973RSPSA.332..199H | s2cid = 121521673
}}
* {{Citation
| publisher = Wiley
| isbn = 978-0471940906
| last = Whitham
| first = G. B.
| title = Linear and nonlinear waves
| year = 1974
}}
{{refend}}