5 References and Suggested Readings. 1 Latter-day Radial links. 1 The Linear Adiabatic Wave Equation. 2 Nonadiabatic Radial movies. 1 The acerbic lb. The Epstein Weight Function and Cepheids. 3 Nonadiabaticity and the Cepheid Strip. A Footnote on Nonlinear Modeling. 3 An llnwiqml to early s.