Cita APA (7a ed.)

Organisation of the Petroleum Exporting Countries [Viena]. (1980). Annual report 1998. OPEC.

Cita Chicago Style (17a ed.)

Organisation of the Petroleum Exporting Countries [Viena]. Annual Report 1998. Viena: OPEC, 1980.

Cita MLA (9a ed.)

Organisation of the Petroleum Exporting Countries [Viena]. Annual Report 1998. OPEC, 1980.