1. California Fuel Cell Partnership (2019) How It Works.
https://cafcp.org/sites/default/files/HowItWorks-Fuel-Cell-Booklet.pdf
. Accessed 10 Apr 2019
2. Tchouvelev A, Hay D, Bénard P (2006) Quantitative risk comparison of hydrogen and CNG refuelling options. Final technical report to Natural Resources Canada
3. United Nations (2013) Global technical regulation on hydrogen and fuel cell vehicles. ECE/TRANS/180/Add.13
http://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29wgs/wp29gen/wp29registry/ECE-TRANS-180a13e.pdf
4. National Fire Protection Association (2010) NFPA 502, standard for road tunnels, bridges, and other limited access highways
5. Code of Federal Regulations. Standard No. 304; Compressed natural gas fuel container integrity. 49 CFR 571.304