| Auteur(s) | Gess, S.K., Gess FW |
| Jaar | 2003 |
| Titel | A catalogue of flower visiting records for aculeate wasps and bees in the semi-arid to arid areas of southern Africa. Albany Museum, Grahamstown, 529 pp. |
| Auteur(s) | Gess, S.K., Gess FW |
| Jaar | 2003 |
| Titel | A catalogue of flower visiting records for aculeate wasps and bees in the semi-arid to arid areas of southern Africa. Albany Museum, Grahamstown, 529 pp. |