Martha Kneib (2007). Chad. Marshall Cavendish, გვ. 20–21. ISBN978-0-7614-2327-0., Quote: "In the past, a key component of Chad's economy was the slave trade" (see photo's caption).
"Chad". Country Reports on Human Rights Practices 2004, 28 February 2005. Bureau of Democracy, Human Rights, and Labor, U.S. Department of State.
"Chad", Country Reports on Human Rights Practices for 2012, Bureau of Democracy, Human Rights and Labor, U.S. Department of State, 26 March 2013. Retrieved 10 February 2014.