ลีลาเกียรติสกุล ว. Problems of VOIP and Spam over Internet Telephony. JOURNAL OF INFORMATION SCIENCE AND TECHNOLOGY, [S. l.], v. 2, n. 1, p. 21–30, 2011. DOI: 10.14456/jist.2011.3. Disponível em: https://ph02.tci-thaijo.org/index.php/JIST/article/view/135164. Acesso em: 25 may. 2024.