Here are entered works on trade among nations. Works on foreign trade of specific countries, cities, etc. are entered under headings of the type [place]--Commerce, further subdivided by place, if appropriate. If so subdivided, a second heading is assigned with the place names in reverse positions, e.g. 1. Canada--Commerce--United States. 2. United States--Commerce--Canada.
Here are entered works on the events, metaphorically referred to as a "war," consisting of military operations, diplomatic activities, and other counterterrorist measures undertaken by the United States during the period from September 11, 2001 to the end of the administration of George W. Bush. Works on government antiterrorist measures and activities during earlier or later periods are entered under Terrorism--Prevention.
This heading may be subdivided geographically for works on the impact of global warming on a particular place. --subdivision Effect of global warming on under individual animals and groups of animals and individual plants and groups of plants, e.g. Fishes--Effect of global warming on; Corn--Effect of global warming on