O'Brien, Patrick Karl (2002). Oxford Atlas of World History (em inglês). [S.l.]: Oxford University Press. pp. 42–43. ISBN9780195219210 Western portion of the Achaemenid Empire appears on page 42, eastern portion on page 43.
Alcock, Susan E.; Alcock, John H. D'Arms Collegiate Professor of Classical Archaeology and Classics and Arthur F. Thurnau Professor Susan E.; D'Altroy, Terence N.; Morrison, Kathleen D.; Sinopoli, Carla M. (2001). Empires: Perspectives from Archaeology and History (em inglês). [S.l.]: Cambridge University Press. p. 105. ISBN9780521770200
brynmawr.edu
repository.brynmawr.edu
The Achaemenid Empire in South Asia and Recent Excavations in Akra in Northwest Pakistan Peter Magee, Cameron Petrie, Robert Knox, Farid Khan, Ken Thomas p.713-714