“Yes to the NRLA”. Bern, Switzerland: Swiss Federal Archives SFA, Swiss Federal Office of Transport FOT, Swiss Confederation. 1992년 12월 1일. 2016년 6월 18일에 확인함.
“Yes to the Alps Initiative”. Bern, Switzerland: Swiss Federal Archives SFA, Swiss Federal Office of Transport FOT, Swiss Confederation. 2016. 2016년 6월 18일에 확인함.
“Yes to public transport funding”. Bern, Switzerland: Swiss Federal Archives SFA, Swiss Federal Office of Transport FOT, Swiss Confederation. 2016. 2016년 6월 18일에 확인함.
“The end of the 28-tonne limit”. Bern, Switzerland: Swiss Federal Archives SFA, Swiss Federal Office of Transport FOT, Swiss Confederation. 2016. 2016년 6월 18일에 확인함.
“Yes to the Ceneri Base Tunnel”. Bern, Switzerland: Swiss Federal Archives SFA, Swiss Federal Office of Transport FOT, Swiss Confederation. 2016. 2016년 6월 18일에 확인함. Federal Councilor Moritz Leuenberger: «This is the only way to make the railway a flat line between Basel and Chiasso.»
Green, Anitra (2017년 8월 4일). “Strong start for Gotthard Base Tunnel”. 《International Railway Journal》 (Falmouth, Cornwall, UK: Simmons-Boardman Publishing Inc.). 2017년 12월 19일에 확인함.
Duc-Quang Nguyen (2016년 6월 6일). “How direct democracy has grown over the decades”. 《swissinfo.ch – a branch of the Swiss Broadcasting Corporation SRG SSR》. Explore 600 national votes (Bern, Switzerland: Swiss Broadcasting Corporation SRG SSR). 2016년 7월 24일에 확인함.