Barbara Hardt · Barbara Hardy · Barbara Howard
| title | ISBN-13 (ISBN-10) | year of publica- tion |
|---|---|---|
| Entering the Stone: On Caves and Feeling Through the Dark | 978-0-618-49229-9 (0-618-49229-1) | 2005 |
| Stirring the Mud: On Swamps, Bogs, and Human Imagination | 978-0-618-21512-6 (0-618-21512-3) | 2003 |