United Nations Department of International Economic and Social Affairs. (1990). International standard industrial classification of all economic activities (3. rev.).
Chicago-Zitierstil (17. Ausg.)United Nations Department of International Economic and Social Affairs. International Standard Industrial Classification of All Economic Activities. 3. rev. New York, 1990.
MLA-Zitierstil (9. Ausg.)United Nations Department of International Economic and Social Affairs. International Standard Industrial Classification of All Economic Activities. 3. rev. 1990.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.