R. Friedman Books in association with the Vulture Study Group · Various small imprints
| title | ISBN-13 (ISBN-10) | year of publica- tion | other author(s) |
|---|---|---|---|
| Dierama: The Hairbells of Africa | 978-1-874802-01-3 (1-874802-01-7) | 1991 | O. M. Hilliard |
| The Botany of the Southern Natal Drakensberg | 978-0-620-10625-2 (0-620-10625-5) | 1987 | " |