References
- Gomory , R.E. 1969 . Some Polyhedra Related to Combinatorial Problems . J. Lin. Algebra and Its Applications , 2 : 451 – 558 .
- Hu , T.C. 1969 . Integer Programming and Network Flows Reading
- Lekkerkerker , G. 1969 . Geometry of Numbers , Amsterdam : Groningen . London