1. According to G. Brux, Safety in road tunnels, Tunnel, 6/2001, 52–61, in the year 2000 up to 10 accidents per km tunnel.
2. W.T.W. Cory, Fans for vehicular tunnels, Tunnels & Tunneling International, September 1998, 62–65
3. G. Teichmann: Fire Protection in Tunnels and Subsurface Transport Facilities, Tunnel 5/1998, 41–46
4. Historische Alpendurchstiche in der Schweiz, Gesellschaft für Ingenieurbaukunst, Band 2, 1996, ISBN 3-7266-0029-9
5. Tunnelling Switzerland, K. Kovári & F. Descoeudres (eds.), Swiss Tunnelling Society, 2001, ISBN 3-9803390-6-8