1. L. D. Landau and E. M. Lifshitz,Fluid Mechanics(Pergamon, Oxford, 1959), Chap. XVI.
2. I. M. Khalatnikov,An Introduction to the Theory of Superfluidity(Benjamin, New York, 1965), Chap. 13.
3. Second Sound in Liquid Helium II
4. Experiments on second-sound shock waves in superfluid helium
5. J. L. Wise, Ph.D. thesis, California Institute of Technology, 1979.