एपीए उद्धरण

Alfaro, M. d. R. (1993). The Air a Resource Without Borders, discussed in Agenda 21.

शिकागो स्टाइल उद्धरण

Alfaro, María del Rosario. The Air a Resource Without Borders, Discussed in Agenda 21. 1993.

एमएलए उद्धरण

Alfaro, María del Rosario. The Air a Resource Without Borders, Discussed in Agenda 21. 1993.