Kalnins, Ernie G.Miller, W., Jr.2008-11-032008-11-031978-06Kalnins, E.G. & Miller, W., Jr. (1978). Lie theory and the wave equation in space–time. 5. R-separable solutions of the wave equation ψtt-∆3ψ=0. Journal of Mathematical Physics, 19, 1247.0022-2488https://hdl.handle.net/10289/1246A detailed classification is made of all orthogonal coordinate systems for which the wave equation ψtt-∆3ψ=0 admits an R-separable solution. Only those coordinate systems are given which are not conformally equivalent to coordinate systems that have already been found in previous articles. We find 106 coordinates to given a total of 368 conformally inequivalent orthogonal coordinates for which the wave equation admits an R separation of variables.application/pdfenCopyright 1978 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in the Journal of Mathematical Physics and may be found at http://jmp.aip.org/jmp/top.jspMathematicsJournal Article10.1063/1.523820