Helmich, H. (1990). Directory of non - governmental development organizations in OECD member countries. OCDE.
Cita Chicago Style (17a ed.)Helmich, Henry. Directory of Non - Governmental Development Organizations in OECD Member Countries. París: OCDE, 1990.
Cita MLA (9a ed.)Helmich, Henry. Directory of Non - Governmental Development Organizations in OECD Member Countries. OCDE, 1990.
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