Cita APA (7th ed.)

United Nations Environment Programme Industry and Environment. (1998). Ecolabels in the tourism industry. UNEP.

Cita Chicago (17th ed.)

United Nations Environment Programme Industry and Environment. Ecolabels in the Tourism Industry. Paris, France: UNEP, 1998.

Cita MLA (9th ed.)

United Nations Environment Programme Industry and Environment. Ecolabels in the Tourism Industry. UNEP, 1998.