Hill, J., & Gale, T. (2009). Ecotourism and environmental sustainability: Principles and practice. Ashgate Publishing Limited.
Chicago Style aipamenaHill, Jennifer, and Tim Gale. Ecotourism and Environmental Sustainability: Principles and Practice. Surrey, England: Ashgate Publishing Limited, 2009.
MLA aipamenaHill, Jennifer, and Tim Gale. Ecotourism and Environmental Sustainability: Principles and Practice. Ashgate Publishing Limited, 2009.
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