Subject
Emigration and immigration law
18
Geology
16
Mines and mineral resources
16
Free trade
15
Mexico Foreign relations
14
United States Foreign relations
14
Drug control
13
Mexico Foreign economic relations
13
Drug traffic
12
United States Foreign economic relations
12
Canada Foreign economic relations
11
Hazard mitigation
11
Emergency management
10
Mexico History
10
Border security
9
Children Legal status, laws, etc
9
Organized crime
9
Mexico Antiquities
8
Mexico Economic conditions
8
National security
8
Paternity
8
Mexico Boundaries
7
Mexico Commerce
7
Mexico Emigration and immigration
7
Real property Foreign ownership
7
United States Commerce
7
Communication of technical information
6
Hazardous substances Law and legislation
6
Indians of Mexico Antiquities
6
Mexico
6
Mexico Politics and government
6
Naturalization
6
Paleontology
6
Rules and practice
6
United States Boundaries
6
Citizenship
5
Hazardous substances Transportation
5
Mexico Relations
5
Tires Recycling
5
Antimony ores
4
Aztecs History
4
Cartels
4
Central America Antiquities
4
Criticism and interpretation
4
Firearms Law and legislation
4
Geology, Stratigraphic
4
Gun control
4
Hazardous wastes Management
4
History
4
Illegal immigration
4
more ...