@article{article2156,
  title = {Matrix geometric method for Markovian queueing model with breakdown, backup server, working vacation and customer impatience},
  author = {P., I. and K., K.},
  journal = {Sigma Journal of Engineering and Natural Sciences},
  year = {2026},
  volume = {44},
  pages = {3231-3245},
  doi = {10.14744/sigma.2026.2156}
}