Exploring our prehistoric Indian ruins : the national archeological monuments of the United States, administered by the National Park Service

Fading trails : the story of endangered American wildlife, prepared by a committee of the united States Department of the interior, National park service, Fish and wildlife service, Daniel B. Beard, chairman, Frederick C. Lincoln [and others]

Ecological theme analysis and inventory of potential natural landmarks of the Great Plains natural region : report to the National Park Service, United States Department of the Interior

Assateague Island National Seashore, Maryland and Virginia

Agate Fossil beds : Agate Fossil Beds National Monument, Nebraska

Underground railroad

Devils Tower : Devils Tower National Monument, Wyoming

Exploring the American West, 1803-1879

Great Smoky Mountains National Park, North Carolina and Tennessee

Grand Teton : a guide to Grand Teton National Park, Wyoming

The Blackfoot

Hawai'i volcanoes.