"Achaemenid Empire." Ancient Persia. 2007. Ancient Persia. 12 Dec 2007 http://www.ancientpersian.com/history/hist_f.htm.
"Achaemenid Empire - Persian Empire." Digital Egypt. 2000. University College London. 12 Dec 2007 http://www.digitalegypt.ucl.ac.uk/maps/persianempire.html.
"Darius the Great." NNDB Tracking the Entire World. 2007. Soylent Communications. 12 Dec 2007 http://www.nndb.com/people/994/000092718/darius-1.
Hatzigeorgiou, Karen. "Persian History." Karen's Whimsy. 2007. Karen's Whimsy. 12 Dec 2007 <http://www.karenwhimsy.com/persianhistory.shtm>.
Meyer, Ronald Bruce. "Cyrus the Great Conquers Babylon (539 B.C.E.): The End of the Babylon "Captivity"." RonaldBruceMeyer.com "The VoiceMan". 2007. Ronald Bruce Meyer. 12 Dec 2007 http://www.ronaldbrucemeyer.com/rants/1029almanac.htm.
Shahmiri, Cyrus. "The Elamite Empire." All Empires Online History Community. 2004. All Empires. 12 Dec 2007 http://www.allempires.com/article/index.php?g=The_Elamite_Empire.