9WILLIS K G,GARROD G D.An individual travel-cost method of evaluating forest recreation[J].Journal of Agricultural Economics,1991,42(1):33-42.
10PAWINEE IAMTRAKUL,KAZUNORI HOKAO,KARDI TEKNOMO.Public park valuation using trayel cost method[J].Proceedings of the Eastern Asia Society for Transportation Studies,2005 (5):1249 -1264.