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"ISDN." Fullformexpand.com, https://www.fullformexpand.com/isdn/861614. Accessed 30 Nov. 2025.
Fullformexpand.com, 2025. "ISDN." Accessed November 30, 2025. https://www.fullformexpand.com/isdn/861614.
"ISDN." (n.d.). Fullformexpand.com. Retrieved November 30, 2025, from https://www.fullformexpand.com/isdn/861614.
ISDN. (2025). Fullformexpand.com. Available at: https://www.fullformexpand.com/isdn/861614 (Accessed: 30 November 2025).