1. [
1
] ITU-T Recommendation I.121 Broadband aspects of ISDN (B-ISDN Protocol Reference Model). Geneva Switzerland 16. June 1993. [1] ITU-T Recommendation I.121 Broadband aspects of ISDN (B-ISDN Protocol Reference Model) . Geneva Switzerland 16. June 1993.
2. [
2
] ITU-T Recommendation I.150 B-ISDN asynchronous transfer mode functional characteristics. Geneva Switzerland 28. March 1994. [2] ITU-T Recommendation I.150 B-ISDN asynchronous transfer mode functional characteristics . Geneva Switzerland 28. March 1994.
3. [
3
] ITU-T Recommendation Q.931 Digital subscriber signalling system no. 1 (DSS 1) -- ISDN user-network interface layer 3 specification for basic call control. Geneva Switzerland 22. November 1994. [3] ITU-T Recommendation Q.931 Digital subscriber signalling system no. 1 (DSS 1) -- ISDN user-network interface layer 3 specification for basic call control . Geneva Switzerland 22. November 1994.
4. [
4
] ITU-T Draft Recommendation Q.2931 Edinburgh TD 155 Broadband Integrated Services Digital Network (B-ISDN) Digital Subscriber Signalling System No. 2 User Network Interface Layer 3 Specification for Basic Call/Connection Control. Geneva Switzerland 13-21. June 1994. [4] ITU-T Draft Recommendation Q.2931 Edinburgh TD 155 Broadband Integrated Services Digital Network (B-ISDN) Digital Subscriber Signalling System No. 2 User Network Interface Layer 3 Specification for Basic Call/Connection Control . Geneva Switzerland 13-21. June 1994.