On a Two-Stage Birth and Death Queueing Process. - Christos Langaris (Oper. Res., 1989)

Waiting time analysis of a two-stage queueing system with priorities. - Christos Langaris (Queueing Syst. Theory Appl., 1993)

Time-dependent analysis of a queue with batch arrivals andn levels of nonpreemptive priority. - Christos Langaris; A. Katsaros (Queueing Syst. Theory Appl., 1995)

A retrial queue with structured batch arrivals, priorities and server vacations. - Christos Langaris; Evangelos Moutzoukis (Queueing Syst. Theory Appl., 1995)

Analysis of a retrial queue with two-phase service and server vacations. - Ioannis Dimitriou; Christos Langaris (Queueing Syst. Theory Appl., 2008)

A repairable queueing model with two-phase service, start-up times and retrial customers. - Ioannis Dimitriou; Christos Langaris (Comput. Oper. Res., 2010)

A queueing system with n-phases of service and (n-1)-types of retrial customers. - Christos Langaris; Ioannis Dimitriou (Eur. J. Oper. Res., 2010)