Surrender or starve : travels in Sudan, Eritrea, Somalia, and Ethiopia / Robert D. Kaplan. (OCLC #52381251)
Though this title is about four different countries, there are more than three of them, so by the rule of three, we include only their broader geographic subject heading:
651 _0 ǂa Africa, Northeast ǂx Description and travel.
The names of the countries are in the title; as they are available from a keyword search, not much subject access is lost by not also including them as subjects.