1. Schrage, L., The Queue M/G/1 with Feedback to Lower Priority Queues, Manag. Sci., 1967, vol. 13, no. 7, pp. 466–474.
2. Yashkov, S.F., The Foreground-Background Processor-Sharing with Minimal Served Length Discipline, Tekh. Sredstv Svyazi. Ser. ASU, 1978, no. 2, pp. 51–62.
3. Pechinkin, A.V., Stationary Probabilities in a System with Foreground-Background Processor-Sharing Discipline, Izv. Akad. Nauk SSSR, Tekh. Kibern., 1980, no. 5, pp. 73–77.
4. Nagonenko, V.A. and Pechinkin, A.V., The Large Traffic Intensity in a System with Foreground-Background Processor-Sharing Discipline, Izv. Akad. Nauk SSSR, Tekh. Kibern., 1980, no. 6, pp. 62–67.
5. Pechinkin, A.V. and Tatashev, A.G., The Generalized Foreground-Background Processor-Sharing Discipline, Izv. Akad. Nauk SSSR, Tekh. Kibern., 1981, no. 4, pp. 120–125.