On the Convex Hull of the Integer Points in a Disc.

Antal Balog Imre Bárány On the Convex Hull of the Integer Points in a Disc. 162-165 1991 Symposium on Computational Geometry http://doi.acm.org/10.1145/109648.109666 db/conf/compgeom/compgeom91.html#BalogB91