UTOMO, S.; AZZQY, A. A. R. Penguasaan FIR (Flight Information Region) di Kepulauan Riau Terkait dengan DCA (Defense Cooperation Agreement) Indonesia-Singapura. Balcony, [S. l.], v. 1, n. 1, p. 63–76, 2017. Disponível em: https://jom.fisip.budiluhur.ac.id/index.php/balcony/article/view/20. Acesso em: 8 sep. 2024.