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Subject Index - Geography


Use U.S. Postal Service abbreviations (such as CO for Colorado and DC for District of Columbia) for states in bibliographies, references, and full addresses (those that include streets or post office boxes).

P.O. Box 123
Denver, CO 80101
In text, when you refer to a state with a city or by itself (for example, "The state energy office is stepping up solar retrofit activities in Massachusetts."), spell out the name of the state in full, except for the District of Columbia (D.C.). See also states and countries.

geographic regions

Don't capitalize words that describe general areas of the country or areas of a state.

the eastern United States
southwestern Nebraska
northern New Mexico

Capitalize directional words when they designate specific or widely known regions; if in doubt, use lowercase.

Southern California
West Texas
the Midwestern states
the South Side of Chicago

phone numbers

Do not use parentheses around area codes in phone numbers. Parentheses previously were used to set off the three-digit code in a phone number because it wasn't always necessary when dialing the number. However, they are required in most instances now.

Use hyphens to separate the digits in phone numbers.



states and countries

1. States

In text, consistently spell out states' names rather than using U.S. Postal Service abbreviations.

California (rather than CA)
Colorado (rather than CO)
Wyoming (rather than WY)

You may use D.C. for the District of Columbia in text, in both formal and informal publications. When you include addresses or state names in full addresses (containing streets and cities), contact lists, reference lists, and bibliographies, however, you may use the following abbreviations:

AL, AK, AZ, AR, CA, CO, CT, DC, DE, FL, GA, HI, ID, IL, IN, IA, KS, KY, LA, ME, MD, MA, MI, MN, MS, MO, MT, NE, NV, NH, NJ, NM, NY, NC, ND, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VT, VA, WA, WV, WI, WY (PR, VI).

2. Countries

Do not abbreviate the names of countries (including the United States) when they are used as nouns. Use "U.S." as the adjective form.

the United States
U.S. Department of Energy program
U.S. population