Note—A Note on Optimal and Near Optimal Price and Advertising Strategies
指出Welam（1982）的离散时间广告模型与Gould（1970）的连续时间模型等价，并引用Rao（1983）的工作来证明这种等价性。
In this paper “Optimal and Near Optimal Price and Advertising Strategies,” Welam (Welam, Ulf P. 1982. Optimal and near optimal prize and advertising strategies. Management Sci. 28 1313–1327.) considers a model which is similar to a model analyzed by Gould (Gould, John P. 1970. Diffusion processes and optimal advertising policy. E. S. Phelps et al., eds. Microeconomic Foundations of Employment and Inflation Theory. W. W. Norton, 338–368.) in his work on optimal advertising policies. The main difference between the two papers is that while Welam's analysis is in discrete time, Gould's is in continuous time. The equivalence of the two analyses is easy to establish and is contained in Rao (Rao, Ram C. 1983. A note on optimal advertising strategies. Working paper, University of Texas, Dallas, January.).