Elonka, Stephen Michael, author
Standard plant operator's questions & answers
McGraw-Hill, 1981
 Buku Referensi
Kettell, Brian, author
Frequently asked questions in Islamic finance
Wiley, 2010
 Buku Teks
Runciman, Lex, author
Asking questions : a rhetoric for the intellectual life
Allyn and Bacon, 1999
 Buku Teks
Medical questions?medline has answers
 Artikel Jurnal
Ching, Hai Wu Shang Shih, author
The Key of immediate enlightenment: questions and answer
The Supreme Master Ching Hai , 1993
 Buku Teks