Zelaya, I. A.; Owen, M. D. K.; Vangessel, M. J. (2007), "Transfer of glyphosate resistance: evidence of hybridization in Conyza (Asteraceae)", American Journal of Botany, 94 (4): 660–73, doi:10.3732/ajb.94.4.660, PMID21636434
Zelaya, I. A.; Owen, M. D. K.; Vangessel, M. J. (2007), "Transfer of glyphosate resistance: evidence of hybridization in Conyza (Asteraceae)", American Journal of Botany, 94 (4): 660–73, doi:10.3732/ajb.94.4.660, PMID21636434