^Kavtaradze, Giorgi L. (2002), An Attempt to Interpret Some Anatolian and Caucasian Ethnonyms of the Classical Sources, pp. 63-83. Sprache und Kultur #3. Staatliche Ilia Tschawtschawadse Universität Tbilisi für Sprache und Kultur. Institut zur Erforschung des westlichen Denkens, Tbilissi.
^Pliny the Elder. Natural History. pp. Book VI, section IV. Archived from the original on 2017-01-01.
^Edwards, Robert W. (1988), The Vale of Kola: A Final Preliminary Report on the Marchlands of Northeast Turkey, p. 129-130. Dumbarton Oaks Papers, Vol. 42.
^M. Inadze, Institute of History, Georgian Academy of Sciences, PROBLEMS OF ETHNOPOLITICAL HISTORY OF ANCIENT ABKHAZIA
^"Апсилы". Bse.sci-lib.com. Retrieved 2013-10-21.
^Alexander Mikaberidze (6 February 2015). Historical Dictionary of Georgia. Rowman & Littlefield Publishers. pp. 130–1. ISBN 978-1-4422-4146-6.