Columbia subject headings:
Silk Road--Economic aspects--21st century.
Syria--History--Civil War, 2011-
Trade routes--Asia.
Harvard subject headings:
Silk roads--Economic aspects--21st century.
Syria--History--Civil War, 2011-
Trade routes--Asia
Princeton subject headings:
Silk roads--Economic aspects--21st century.
Syria--History--Civil War, 2011-
Trade routes--Asia.