Columbia subject headings:
Ereğli (Zonguldak İli, Turkey)--History.
Iron industry and trade--Turkey.
Labor unions--Turkey--History--20th century.
Labor unions--Turkey--History.
Labor--Turkey--Zonguldak--History.
Steel industry and trade--Turkey.
Harvard subject headings:
Ereğli (Zonguldak İli, Turkey)--History.
Iron industry and trade--Turkey.
Labor unions--Turkey--History--20th century.
Labor unions--Turkey--History.
Labor--Turkey--Zonguldak--History.
Steel industry and trade--Turkey.
Princeton subject headings:
Ereğli (Zonguldak İli, Turkey)--History.
Iron industry and trade--Turkey.
Labor unions--Turkey--History--20th century.
Labor unions--Turkey--History.
Labor--Turkey--Zonguldak--History.
Morrison Knudsen Corporation.
Steel industry and trade--Turkey.