References
For Acicarpha
DeVore, M.L. 1991. The occurrence of Acicarpha tribuloides (Calyceraceae) in eastern North America. Rhodora 93: 26-35. Google Scholar
Hellwig. 2007. In Kadereit, J.W., and C. Jeffrey. 2007. The families and genera of vascular plants. VIII. Flowering plants – Eudicots – Asterales. Springer, Berlin. 636 pp. Google Scholar