Holmlund, Per (15 January 2007). «Tarfala in numbers». Department of Physical Geography and Quaternary Geology. Arkivert frå originalen den 21 March 2012. Henta 21 March 2012.
Holmlund, Per (15 January 2007). «Tarfala in numbers». Department of Physical Geography and Quaternary Geology. Arkivert frå originalen den 21 March 2012. Henta 21 March 2012.