Stackelberg and Marshall
提出一个广义的N企业斯塔克尔伯格模型作为寡头垄断的可检验替代描述，证明当企业规模相对于需求缩小时，效率在极限中实现，适用于U形平均成本和自然垄断情形。
This paper advocates a generalized N-firm Stackelberg model as a plausible testable alternative description of oligopoly. A pure-strategy equilibrium must exist for this model. The main result is that efficiency obtains in the limit as the scale of each firm is shrunk relative to demand. This is demonstrated for the case of U-shaped average cost and also for that of natural monopoly. Copyright 1990 by American Economic Association.