Echinocactus horizonthalonius f. curvispinus (Salm-Dyck) Schelle
, Handb. Kakteenkult. 146 (1907). BHL
External links to taxonomic opinions:
- IPNI Life Sciences Identifier (LSID)
- urn:lsid:ipni.org:names:87438-2
- Publication
- Handbuch der Kakteenkultur.
- Collation
- 146
- Family as entered in IPNI
- Cactaceae