We consider a class of multi-periodic non-stationary stochastic single-product inventory planning problems where two procurement modes can be used at each period: a first order with immediate delivery and a second order with a single-period delivery delay. Clearly, the slow delivery mode is less...

A proposed single-product, stochastic, two-period inventory control model combines demand forecast updating with the flexibility of two supply sources. Demand is modeled by two independent, random variables over a two-period selling season. At the beginning of the first period, two quantities...