Ferreira, P. D. L., Antonelli, A., & Groppo, M. (2021).

Touch me carefully: a step towards understanding morphological diversity in the South American spiny sunflowers (Compositae, Barnadesioideae)

. Phytotaxa, 518(2), 109–142. https://doi.org/10.11646/phytotaxa.518.2.3