English, Nathan B; Dettman, David L; Sandquist, Darren R; Williams, David G (2007). "Past climate changes and ecophysiological responses recorded in the isotope ratios of saguaro cactus spines". Oecologia. 154 (2): 247–258. Bibcode:2007Oecol.154..247E. doi:10.1007/s00442-007-0832-x. PMID17724618. S2CID282478.
Delgado-Fernández, Mariana; Garcillán, Pedro P; Ezcurra, Exequiel (2016). "On the Age and Growth Rate of Giant Cacti: Radiocarbon Dating of the Spines of Cardon (Pachycereus Pringlei)". Radiocarbon. 58 (3): 479–490. Bibcode:2016Radcb..58..479D. doi:10.1017/RDC.2016.25. S2CID130664993.
Hultine, Kevin R; Dettman, David L; English, Nathan B; Williams, David G (2019). "Giant cacti: isotopic recorders of climate variation in warm deserts of the Americas". Journal of Experimental Botany. 70 (22): 6509–6519. doi:10.1093/jxb/erz320. PMID31269200.
English, Nathan B; Dettman, David L; Sandquist, Darren R; Williams, David G (2007). "Past climate changes and ecophysiological responses recorded in the isotope ratios of saguaro cactus spines". Oecologia. 154 (2): 247–258. Bibcode:2007Oecol.154..247E. doi:10.1007/s00442-007-0832-x. PMID17724618. S2CID282478.
Delgado-Fernández, Mariana; Garcillán, Pedro P; Ezcurra, Exequiel (2016). "On the Age and Growth Rate of Giant Cacti: Radiocarbon Dating of the Spines of Cardon (Pachycereus Pringlei)". Radiocarbon. 58 (3): 479–490. Bibcode:2016Radcb..58..479D. doi:10.1017/RDC.2016.25. S2CID130664993.
English, Nathan B; Dettman, David L; Sandquist, Darren R; Williams, David G (2007). "Past climate changes and ecophysiological responses recorded in the isotope ratios of saguaro cactus spines". Oecologia. 154 (2): 247–258. Bibcode:2007Oecol.154..247E. doi:10.1007/s00442-007-0832-x. PMID17724618. S2CID282478.
Hultine, Kevin R; Dettman, David L; English, Nathan B; Williams, David G (2019). "Giant cacti: isotopic recorders of climate variation in warm deserts of the Americas". Journal of Experimental Botany. 70 (22): 6509–6519. doi:10.1093/jxb/erz320. PMID31269200.
English, Nathan B; Dettman, David L; Sandquist, Darren R; Williams, David G (2007). "Past climate changes and ecophysiological responses recorded in the isotope ratios of saguaro cactus spines". Oecologia. 154 (2): 247–258. Bibcode:2007Oecol.154..247E. doi:10.1007/s00442-007-0832-x. PMID17724618. S2CID282478.
Delgado-Fernández, Mariana; Garcillán, Pedro P; Ezcurra, Exequiel (2016). "On the Age and Growth Rate of Giant Cacti: Radiocarbon Dating of the Spines of Cardon (Pachycereus Pringlei)". Radiocarbon. 58 (3): 479–490. Bibcode:2016Radcb..58..479D. doi:10.1017/RDC.2016.25. S2CID130664993.