engert, m. (1964). classification of industries in social countries. the institute of national planning.
Čikaški stil citiranja (17. izdanje)engert, manfred. Classification of Industries in Social Countries. cairo: the institute of national planning, 1964.
MLA način citiranja (9. izdanje)engert, manfred. Classification of Industries in Social Countries. the institute of national planning, 1964.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.