Measuring the economic value of restoring ecosystem services in Zhangye city of Heihe river basin—Comparison and application of continuous and discrete contingent valuation survey
ZHANG Zhi-qiang, XU Zhong-min, LONG Ai-hua, GONG Zeng-tai
JOURNAL OF NATURAL RESOURCES . 2004, (2): 230 -239 .  DOI: 10.11849/zrzyxb.2004.02.014