1. Gilson, K.A. and Khandelwal, D.K., Getting More from Call Centers, The McKinsey Quarterly (online journal), 2005. Available at http://www.mckinseyquarterly.com/getting-more-from-call-centers-1597 .
2. Akşin, O.Z., Armony, M., and Mehrotra, V., The Modern Call Centers: A Multi-Disciplinary Perspective on Operations Management Research, Working Paper, Koç University, Istanbul, Turkey, 2007.
3. Garnett, O., Mandelbaum, A., and Reiman, M., Designing a Call Center with Impatient Customers, Manuf. Serv. Oper. Manag., 2002, vol. 4, no. 3, pp. 208–227.
4. Mandelbaum, A. and Zeltyn, S., Staffing Many-Server Queues with Impatient Customers: Constraint Satisfaction in Call Centers, Working Paper, Technion — Israel Inst. of Technology, 2007.
5. Whitt, W., Sensitivity of Performance in the Erlang A Model to Changes in the Model Parameters, Oper. Res., 2006, vol. 54, no. 2, pp. 247–260.