9Edwin E Krttmpe. Research On Recreation Trails and Trail Users. [EB/OL].http://www.amerieantrails.org/resourees/info/PCAObibliog. html,2008-10-08. 被引量:1
10Ellen Eubanks. Trail Construction and Maintenance Notebook[R]. Washington, DC: United States Department of agrieulttLre, 2004. 1-134. 被引量:1