APA Citation

National five digit zip code & post office directory. Washington, D.C.: United Communications Group, National Information Data Center.

Chicago Style Citation

National Five Digit Zip Code & Post Office Directory. Washington, D.C.: United Communications Group, National Information Data Center.

MLA Citation

National Five Digit Zip Code & Post Office Directory. Washington, D.C.: United Communications Group, National Information Data Center.

Warning: These citations may not always be 100% accurate.