Columbia subject headings:
Harvard subject headings:
Mexico--Foreign economic relations--Pacific Area--Congresses.
Pacific Area--Foreign economic relations--Mexico--Congresses.
Ports of entry--Mexico--Topolobampo--Congresses.
Topolobampo (Mexico)--Foreign economic conditions--Congresses.
Topolobampo (Mexico)--Foreign economic relations--Congresses.
Princeton subject headings:
Mexico--Foreign economic relations--Pacific Area--Congresses.
Pacific Area--Foreign economic relations--Mexico--Congresses.
Ports of entry--Mexico--Topolobampo--Congresses.
Topolobampo (Mexico)--Foreign economic conditions--Congresses.