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9412 Studies found for: REQUIRE

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Map Legend
Region Name Number of Studies
World 9,412
Africa [map] 346
Central America [map] 107
East Asia [map] 837
Japan 239 [studies]
Europe [map] 2,811
Middle East [map] 491
North America 4,646
Canada [map] 965 [studies]
Mexico 175 [studies]
United States [map] 3,972 [studies]
North Asia [map] 294
Pacifica [map] 330
South America [map] 380
South Asia [map] 196
Southeast Asia [map] 270

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Studies with no locations are not included in the counts or on the map.

Studies with multiple locations are included in each region containing locations.