Hilbert's fourth problem /
Pogorelov, Alekseĭ Vasil'evich.
Silverman, Richard A.(Richard Allan)
Kra, Irvin.
Zaustinskiy, Eugene.
Washington, D.C. V.H. Winston and Sons New York London Distributed by Wiley
1979
'A Halsted Press book'
Translation of: 'Chetvertaia problema Gil'berta'. Moskva : Nauka, 1974
Bibliography: p.93-94. - Includes index
Geometry