An official website of the United States GovernmentHere’s how you know
Official websites use .govA .gov website belongs to an official Government organization in the United States.
Secure .gov websites use HTTPS
A lock or https:// means you’ve safely connected to the .gov website.
Share sensitive information only on official, secure websites.
How to Use the Digital Library of the State of the Environment on the Web and on a Web-Connected CD/
Presentation by Dr. Brand L. Niemann, U.S. Environmental Protection Agency.
