An M/PH/k retrial queue with finite number of sources. - Attahiru Sule Alfa; K. P. Sapna Isotupa (Comput. Oper. Res., 2004)

An (s, Q) Markovian inventory system with lost sales and two demand classes. - K. P. Sapna Isotupa (Math. Comput. Model., 2006)

Flow control in capacity-constrained queueing systems with non-stationary arrivals. - Michael A. Haughton; K. P. Sapna Isotupa (J. Oper. Res. Soc., 2013)

A continuous review (s, Q) inventory system with priority customers and arbitrarily distributed lead times. - K. P. Sapna Isotupa; Sujit Kumar Samanta (Math. Comput. Model., 2013)

Cost analysis of an (S-1, S) inventory system with two demand classes and rationing. - K. P. Sapna Isotupa (Ann. Oper. Res., 2015)

Continuous review (s, Q) inventory system at a service facility with positive order lead times. - Sujit Kumar Samanta; K. P. Sapna Isotupa; A. Verma (Ann. Oper. Res., 2023)