The tribe was mentioned by Pliny the Elder in his Naturalis Historia, and it borrowed its name to one of the Roman cities on the coast, Lopsica (present day Sveti Juraj in Croatia). The name has survived to present day as a place name, as well as the family surname Lopac.
- Wilkes, J. J. The Illyrians, 1992, ISBN 0-631-19807-5,page 95
- The Cambridge Ancient History by Alan K. Bowman,ISBN 0521264308, page 575
- Naturalis Historia.
- "PLINII NATVRALIS HISTORIAE LIBER III". Retrieved 2008-07-16.
- "Pliny the Elder, The Natural History, BOOK III. AN ACCOUNT OF COUNTRIES, NATIONS, SEAS, TOWNS, HAVENS, MOUNTAINS, RIVERS, DISTANCES, AND PEOPLES WHO NOW EXIST OR FORMERLY EXISTED., CHAP. 25. (21.)—LIBURNIA AND ILLYRICUM". Retrieved 2017-11-09.