- ISDN Tutorial: History, concepts, references, and more ...www.ralphb.net/ISDN
- COMMON-ISDN-API: CAPI - the ISDN interface ...www.capi.org
- Jeff Frohwein's ISDN Technical Page Schematics AT&T NT-1 Application Note ISDN Hardware ADTRAN Isdn Products Motorola BitSurfer ISDN Software UPA U Interface Protocol Analyzer ISDN Standards WinISDN Reference ...fly.hiwaay.net/~jfrohwei/isdn
