Rindzevičius, R., D. Poškaitis, and B. Dekeris. “Performance Measures Analysis of M/M/M/K/N Systems With Finite Customer Population”. Elektronika Ir Elektrotechnika, vol. 67, no. 3, Mar. 2006, pp. 65-70, https://eejournal.ktu.lt/index.php/elt/article/view/10635.