Nightingale, Florence
Notes on nursing: What it is, and what it is not
Churchill livingstone , 1980
 Buku Teks SO
Horrie, Chris
What is Islam?
Virgin Books, 1991
 Buku Teks SO
Ahmed, Qadeeruddin
What is riba?
Justice (Retd.) Qadeeruddin Ahmed, 1994
 Buku Teks SO
Sartre, Jean-Paul
What is literature?
Routledge classics, 2001
 Buku Teks SO
Aronoff, Mark
What is morphology?
Blackwell, 2005
 Buku Teks SO