Theory of Vertical Control with Variable Proportions
分析投入品垄断者纵向一体化对最终产品价格和派生需求的影响，发现替代弹性小于1时最终产品价格可能下降，但非垄断投入的派生需求必然减少。
The effect of vertical integration by an input monopolist on the price of the final product and the derived demands are examined when the production is of CES and the demand for the final product is of constant elasticity. The results are proved by analytical methods. Specifically, when the elasticity of substitution is less than one, the price of the final product can decrease but, regardless of any conditions, the derived demand for the nonmonopolized input decreases. However, that of monopolized input decreases if and only if the elasticity of substitution exceeds the elasticity of demand.