地理科学进展
Tourism Spatial Model Study Based on the Gradient Difference of River Basin and Tourism Development in the Xijiang Economic Belt of Guangxi
WEI Zhichao, NIU Yafei, CHEN Tian
PROGRESS IN GEOGRAPHY . 2011, (10): 1321 -1328 .  DOI: 10.11820/dlkxjz.2011.10.015