References
- Ber. Verh. Sa chs. Akad. Wiss. Leipzig Math-Naturw. KI v.68 Raumliche Variationsprobleme mit symmetricher Transversalit-atsbedingung W. Blaschke
- Amer. J. Math. v.71 The isoperimetric problem for Minkowski area H. Busemann
- Convexity and Its Applications Convex bodies of constant width G. D. Chakerian;Groemer;P. M. Gruber(ed.);J. M. Wills. Birkhauser(ed)
- Amer. Math. Monthly v.64 Curves with a kind of constant width P. J. Kelly
- Convex Bodies: The Brunn-Minkowski Theory R. Schneider
- Minkowski geometry A. C. Thomson