Doerr, S. H. (18. март 1999). „Karst-like landforms and hydrology in quartzites of the Venezuelan Guyana shield: Pseudokarst or „real” karst?”. Zeitschrift für Geomorphologie. 43 (1): 1—17. Bibcode:1999ZGm....43....1D. doi:10.1127/zfg/43/1999/1.
Billi, Andrea; De Filippis, Luigi; Poncia, Pier Paolo; et al. (фебруар 2016). „Hidden sinkholes and karst cavities in the travertine plateau of a highly-populated geothermal seismic territory (Tivoli, central Italy)”. Geomorphology. 255: 63—80. Bibcode:2016Geomo.255...63B. doi:10.1016/j.geomorph.2015.12.011.CS1 одржавање: Формат датума (веза)
harvard.edu
adsabs.harvard.edu
Doerr, S. H. (18. март 1999). „Karst-like landforms and hydrology in quartzites of the Venezuelan Guyana shield: Pseudokarst or „real” karst?”. Zeitschrift für Geomorphologie. 43 (1): 1—17. Bibcode:1999ZGm....43....1D. doi:10.1127/zfg/43/1999/1.
Billi, Andrea; De Filippis, Luigi; Poncia, Pier Paolo; et al. (фебруар 2016). „Hidden sinkholes and karst cavities in the travertine plateau of a highly-populated geothermal seismic territory (Tivoli, central Italy)”. Geomorphology. 255: 63—80. Bibcode:2016Geomo.255...63B. doi:10.1016/j.geomorph.2015.12.011.CS1 одржавање: Формат датума (веза)
utexas.edu
esi.utexas.edu
„What is Karst?”(PDF). Environmental Science Institute. The University of Texas at Austin. 16. 5. 2006. Приступљено 25. 12. 2020.CS1 одржавање: Формат датума (веза)