Um víða veröld, Höfundur: Hilmar Egill Sveinbjörnsson, Útgefandi, Námsgagnastofnun, 2015.
https://innrigerdjardar01.weebly.com/heitir-reitir.html
https://is.wikipedia.org/wiki/Heitur_reitur
https://is.wikipedia.org/wiki/Möttulstrókur
https://www.stjornufraedi.is/solkerfid/jordin/
http://www.mr.is/~gk/jfr/ordskyr/r/landrek_steingervingar.htm
http://hawaiipublicradio.org/post/hawaiian-volcano-observatory-back-service
https://innrigerdjardar01.weebly.com/heitir-reitir.html
https://is.wikipedia.org/wiki/Heitur_reitur
https://is.wikipedia.org/wiki/Möttulstrókur
https://www.stjornufraedi.is/solkerfid/jordin/
http://www.mr.is/~gk/jfr/ordskyr/r/landrek_steingervingar.htm
http://hawaiipublicradio.org/post/hawaiian-volcano-observatory-back-service