Note 3451 — BOOK V. AN ACCOUNT OF COUNTRIES, NATIONS, SEAS, TOWNS, HAVENS, MOUNTAINS, RIVERS, DISTANCES, AND PEOPLES WHO NOW EXIST OR FORMERLY EXISTED.
John Bostock translation
Discera was the Im-Zerah of modern travellers, on the road from Sockna to Mourzouk, according to Marcus, who is of opinion that the places which follow were situate at the east and north-east of Thuben and the Black Mountain.