1. Hierarchical integration of production planning and scheduling;Hax,1975
2. Hierarchical production planning systems;Hax,1978
3. Hierarchical production planning: A single stage system;Bitran;Oper. Res.,1982
4. Hierarchical production planning: A two stage system;Bitran;Oper. Res.,1982
5. Why Japanese factories work;Hayes;Harvard Business Review,1981