1. Azzam Y (1987) Join the Caravan https://ebooks.worldofislam.info/ebooks/Jihad/Join%20the%20Caravan.pdf . Accessed 15 April 2015
2. Bakker E, Paulussen C, Entenmann E (2013) Dealing with European foreign fighters in Syria: governance challenges and legal implications. ICCT Research paper www.icct.nl/download/file/ICCT-Bakker-Paulussen-Entenmann-Dealing-With-European-Foreign-Fighters-in-Syria.pdf . Accessed 16 June 2015
3. Barrett R (2014) Foreign fighters in Syria. The Soufan Group www.soufangroup.com/wp-content/uploads/2014/06/TSG-Foreign-Fighters-in-Syria.pdf . Accessed 16 June 2015
4. Byman D, Shapiro J (2014) Be afraid. Be a little afraid: the threat of terrorism from foreign fighters in Syria and Iraq. Brookings, Policy Paper 34
5. Gartenstein-Ross D, Barr N (2015) Dignity and dawn: Libya’s escalating civil war, ICCT Research Paper, February 2015. www.icct.nl/download/file/ICCT-Gartenstein-Ross-Barr-Executive-Summary-Libyas-Escalating-Civil-War-February2015.pdf . Accessed 16 June 2015