1. An integrable shallow water equation with peaked solitons;Camassa;Phys. Rev. Lett.,1993
2. A. Constantin, A general-weighted Sturm–Liouville problem, Annali Sc. Norm. Sup. Pisa
3. A. Constantin, H. P. Kean, A shallow water equation on the circle, Comm. Pure. Appl. Math.
4. Integrable Systems and Algebraic Curves;McKean,1979
5. The spectrum of Hill's equation;McKean;Invent. Math.,1975