VINGARZAN, D., WEIK, P. ., & MAGEDANZ, T. . (2007). DEVELOPMENT OF AN OPEN SOURCE IMS CORE FOR EMERGING IMS TESTBEDS, THE ACADEMIA AND BEYOND. Journal of Mobile Multimedia, 3(2), 131–149. Retrieved from https://journals.riverpublishers.com/index.php/JMM/article/view/4909