Ali, Mohamed bin
The roots of religious extremism: understanding the Salafi Doctrine of Al-Walaʼ wal Baraʼ
Imperial College Press, 2016
 Buku Teks
Schoub, Barry D.
AIDS & HIV in perspective : a guide to understanding the virus and its consequences / Barry D. Schoub.
The University Press, 1999
 Buku Teks
Berlin, Isaiah
The Roots of romanticism
Princeton University Press, 2001
 Buku Teks
Rose, Arnold M.
The roots of prejudice
UNESCO, 1951
 Buku Teks
India's roots of democracy
Carl C. Taylor ... [and others]
Orient Longmans, 1965
 Buku Teks