Lost City of the Incas (Phoenix Press)
Galapagos: A Natural History, Revised and Expanded
Stone Offerings: Machu Picchu's Terraces of Enlightenment
Wildlife of the Galápagos: Second Edition (Princeton Pocket Guides)
People of Chaco: A Canyon and Its Culture (Revised and Updated)
Turn Right at Machu Picchu: Rediscovering the Lost City One Step at a Time
The Incas: People of the Sun