4John Vidal,Annie Kelly. Bhutan set to plough lone furrow as world's first wholly organic country[N].guardian.co.uk,2013.
二级参考文献7
1Florida History, Florida Dept. of Commerce, Tallahasse 1986.
2Florida A Time for Reckoning, National Geographic, Aug. 1982.
3Florida Attractions Association, 2009.
4Florida Department of Revenue, Office of Tax Research Data as reported in Visit Florida, 2001.Visit Florida Studies. 2001.
5A Global Database of Domestic and International Tourist Numbers at National and Subnational Level, Andrea Bigano, Jaequeline M. Hamilton, Maren Lau, Richard S.J. Tol and Yuan Zhou. NOTA DI LAVORO, 3. 2005.
