1. Rosseland, S. (1949) The Pulsation Theory of Variable Stars ( Clarendon, Oxford )
2. Ledoux, P., Walraven, T. (1958) Variable stars, Handb. Physik
50, 353
3. Ledoux, P. (1958) Stellar stability, Handb. Phys. 50, 605
4. Cox, J.P. (1967) The linear theory: initiation of pulsational instability in stars, in Aerodynamic Phenomena in Stellar Atmospheres, IAU Symp. 28, ed. by R.N. Thomas ( Willmer Brothers, Birkenhead, UK )
5. Christy, R.F. (1968) The theory of Cepheid variability, Q. J. R. Astron. Soc. 9, no. 1, p. 13