| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| Geranium Family Species Check List: Part 4 | 978-1-899742-00-4 (1-899742-00-X) | 1985 |
| Pelargonium Species Checklist: Geraniaceae Knuth tribe 1 Geranieae, Pelargonium Pt. 4 | 978-1-899742-60-8 (1-899742-60-3) | 2004 |