In a recent paper [Lemoine, A. J. 1977. Networks of queues--a survey of equilibrium analysis. Management Sci. 24 (4) 464-481.], A. J. Lemoine has derived an expression for the Laplace transform of the residence time T of a customer in a feed-forward exponential network. That expression was used...

We argue the importance of studying service systems in which the successful completion of job/customer service cannot be observed contemporaneously. Military and other applications are cited. The allocation of a large amount of processing to a job may make its (unobservable) successful...