1. Linear programming and extensions;Dantzig,1963
2. Linear programming: methods and applications;Gass,1985
3. Cycling in the simplex algorithm, 1953;Hoffman,1953
4. Comments on the possibility of cycling with the simplex method;Gass;Operations Research,1979
5. Cycling in the dual simplex method;Beale;Naval Research Logistics Quarterly,1955