Columbia subject headings:
Harvard subject headings:
Defectors--Iraq--Biography.
Defectors--Syria--Biography.
IS (Organization)--Biography.
Terrorism--History--21st century.
Terrorism--Religious aspects--Islam
Terrorists--Iraq--Biography.
Terrorists--Syria--Biography.
Princeton subject headings:
Defectors--Iraq--Biography.
Defectors--Syria--Biography.
IS (Organization)--Biography.
Terrorism--History--21st century.
Terrorism--Religious aspects--Islam.
Terrorists--Iraq--Biography.
Terrorists--Syria--Biography.