Cita APA

United Nations Conference on Environment and Development Rio de Janeiro, Brazil, World Travel & Tourism Council, World Tourism Organization, & Earth Council. (1992). Agenda 21 for the travel & tourism industry: Towards environmentally sustainable development. WTTC.

Citación estilo Chicago

United Nations Conference on Environment and Development Rio de Janeiro, Brazil, World Travel & Tourism Council, World Tourism Organization, and Earth Council. Agenda 21 for the Travel & Tourism Industry: Towards Environmentally Sustainable Development. [Brazil: WTTC, 1992.

Cita MLA

United Nations Conference on Environment and Development Rio de Janeiro, Brazil, et al. Agenda 21 for the Travel & Tourism Industry: Towards Environmentally Sustainable Development. WTTC, 1992.