Columbia subject headings:
Labor unions--Canada--Directories.
Labor unions--Canada--Membership--Periodicals.
Labor unions--Canada--Periodicals.
Labor unions--Canada.
Harvard subject headings:
Labor unions--Canada--Directories.
Labor unions--Canada--Membership--Periodicals.
Labor unions--Canada--Periodicals.
Princeton subject headings:
Labor unions--Canada--Directories.
Labor unions--Canada--Handbooks, manuals, etc.