| Titel | ISBN-13 | Erscheinungsjahr |
|---|---|---|
| The Genus Sclerocactus | 978-3-00-016153-7 | 2005 |
| Yucca III Mexico. With Seed Morphology by Dr. Günter Hentzschel. English Translation by Chris Holland | 978-3-00-013124-0 | 2004 |
| Yucca II . Indehiscent-fruited species in the Southwest, Midwest and East of the USA. With Seed Morphology by Dr. Günter Hentzschel | 978-3-00-009008-0 | 2002 |
| Yucca I in the Southwest and Midwest of the USA and Canada. With Seed Morphology by Dr. Günter Hentzschel. English Translation by Chris Holland | 978-3-00-005946-9 | 2000 |