See, for example, Cyril Aldred, The Egyptians (London: Thames and Hudson, rev. ed. 1984), pp. 151, 191–192 and figs. 104 and 134. For a good summary on Nubian mercenaries in First Intermediate period Egypt, see Bruce Trigger, Nubia Under the Pharaohs (Boulder, CO: Westview, 1976), pp. 60–63. For a good estimate on the proportion of foreigners in the Egyptian army in the Ramesside period (c. 1279–1212 B.C.E.) see Papyrus Anastasi I, translated in Ancient Near Eastern Texts, ed. James B. Pritchard (Princeton, NJ: Princeton Univ. Press, 3rd ed., 1969), p. 476.