\ Myths and Counterexamples in Integer Programming and Combinatorial Optimization
\ Harvey J. Greenberg
Maximize
  0 x1
Subject To
  + 2 x1 + 2 x2 + 2 x3 + 2 x4 + 2 x5 + 2 x6 + 2 x7 + 2 x8 + 2 x9 = 9
Binary
  x1 x2 x3 x4 x5 x6 x7 x8 x9
End