共 36 条
[23]
*NAT HIGHW TRAFF S, 2003, NAT SURV PED BIC ATT
[24]
Nelson AC., 1997, TRANSPORT RES REC, V1578, P79, DOI DOI 10.3141/1578-10
[26]
*POP RES CTR, 2008, 2007 OR POP REP
[27]
Pucher J, 2000, TRANSPORT Q, V54, P25