References
- Convexity and its applications Convex bodies of constant width G. D. Chakerian;H. Groemer;P. M. Gruber(ed.);J. M. Wills(ed.)
- Modern differential geometry of curves and surfaces A. Gray
- Handbook of convex geometry P. M. Gruber;J. M. Wills
- Amer. Math. Monthly v.64 Curves with a kind of constant width Paul J. Kelly
- Integral geometry and geometric probability L. A. Santalo
- Convex figures I. M. Yaglom;V. G. Boltyanskii