Keith, DA; Iliffe, TM; Gerovasileiou, V; Gonzalez, B; Brankovits, D; Martínez García, A (2020). "S1.2 Endolithic systems". In Keith, D.A.; Ferrer-Paris, J.R.; Nicholson, E.; Kingsford, R.T. (eds.). The IUCN Global Ecosystem Typology 2.0: Descriptive profiles for biomes and ecosystem functional groups. Gland, Switzerland: IUCN. doi:10.2305/IUCN.CH.2020.13.en. ISBN 978-2-8317-2077-7. S2CID 241360441. 978-2-8317-2077-7