Andreas Brieden Peter Gritzmann Ravi Kannan Victor Klee László Lovász Miklós Simonovits Approximation of Diameters: Randomization Doesn't Help. 244-251 1998 FOCS http://dlib.computer.org/conferen/focs/9172/pdf/91720244.pdf db/conf/focs/focs98.html#BriedenGKKLS98