APA استشهاد

Keesing,Donald B. (1979). Trade policy for developing countries. World Bank.

استشهاد بنمط شيكاغو

Keesing,Donald B. Trade Policy for Developing Countries. Washington: World Bank, 1979.

MLA استشهاد

Keesing,Donald B. Trade Policy for Developing Countries. World Bank, 1979.