9Zietsman J, Bari M E, Rand A J. Feasibility of landfill gas as a liquefied natural gas fuel source for refuse trucks[J]. Air & Waste Manage, 2008: 613-619.
10Kong Fansen, Wang Jun, Sun Haigang. Fuzzy compre- hensive evaluation of equipment usability of engine cylin- der block production line based on AHP[J]. Journal of JilinUniversity: Engineering and Technology Edition, 2008, 38(6) : 1332-1336.