This paper deals with the planning of a production group, which has to produce several products. For each product there is a delivery plan covering several periods. Moreover, there are capacity constraints. Such a situation requires integrated optimization of lot sizes and lot scheduling. Since exact solution of the problem is in general not feasible, we will present a non exact approach which gives quite good results in some practical cases and might be a good starting point in other cases.
van Nunen, J. A. E. E., & Wessels, J. (1978). Multi-item lot size determination and scheduling under capacity constraints. European Journal of Operational Research, 2(1), 36-41. https://doi.org/10.1016/0377-2217(78)90121-2