Columbia subject headings:
Rubber industry and trade--Bibliography.
Rubber industry and trade--Directories.
Rubber industry and trade--Information services--Directories.
Rubber industry and trade--Information services.
Harvard subject headings:
Rubber industry and trade--Bibliography.
Rubber industry and trade--Directories.
Rubber industry and trade--Information services--Directories.
Princeton subject headings:
Rubber industry and trade--Bibliography.
Rubber industry and trade--Directories.
Rubber industry and trade--Information services.