U.S. Agency for International Development. (1990). List of rgistered PVO's with USAID. June 1.
Citazione stile Chigago Style (17a edizione)U.S. Agency for International Development. List of Rgistered PVO's with USAID. Manila: June 1, 1990.
Citatione MLA (9a ed.)U.S. Agency for International Development. List of Rgistered PVO's with USAID. June 1, 1990.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.