The problem of determining the economic production quantity in a multi-stage production system has received little
attention from management scientists. The analysis of
multi-stage production systems is more difficult than the
analysis of single-stage production systems due to the presence of work-in-process inventory. For a detailed descript
ion of the problem of determining economic production quantities in multi-stage production systems and for earlier
approaches for tackling the problem under various situations
see Crowston, Wagner and Williams