IDG Books,

U.S. Environmental Protection Agency : [For sale by the U.S. G.P.O., Supt. of Docs.,

Mosby Year Book,

Corporation for Public Broadcasting],

Annenburg/CPB Collection,

The University,

Concept Media,

U.S. Dept. of Health and Human Services, Public Health Service, Food and Drug Administration, Center for Drugs and Biologics ; For sale by the Supt. of Docs., U.S. G.P.O.,

Johnson Pub. Co.,

Rand McNally,

Concept Media,

University of Wyoming, Geological Survey of Wyoming,