APA Style

Boo, Elizabeth. (1990). Ecotourism . Washington: .

Chicago Style

Boo, Elizabeth. Ecotourism. Washington: , 1990. .

MLA Style

Boo, Elizabeth. Ecotourism. Washington: , 1990. .

Turabian Style

Boo, Elizabeth. Ecotourism. Washington: , 1990. .