APA (7th ed.) Citation

United Nations Environment Programme. (1990). Sand and gravel extraction projects. The Programme.

Chicago Style (17th ed.) Citation

United Nations Environment Programme. Sand and Gravel Extraction Projects. Nairobi, Kenya: The Programme, 1990.

MLA (9th ed.) Citation

United Nations Environment Programme. Sand and Gravel Extraction Projects. The Programme, 1990.

Warning: These citations may not always be 100% accurate.