by Charles Johnston
by Arnauld d' Abbadie
by H. G. C. (Harald G. C.) Swayne
by Richard Andree
by Sir William Cornwallis Harris
by James Bruce
by Charles Johnston
by James Bruce
by Sir Francis Bond Head
by James Bruce
by Giuseppe Vigoni
by Gerhard Rohlfs
by James Bruce
by Sir Samuel White Baker
by Earl of Dermot Robert Wyndham Bourke Mayo