Langer, Maria
Quicken 2000 : the official guide
Osborne/McGraw-Hill, 1999
 Buku Referensi
Stein, Lincoln D.
Official guide to programming with CGI.pm
Wiley, 1998
 Buku Teks SO
Volitich, Dan; Oehler, Karsten
IBM Cognos TM1 : the official guide
McGraw-Hill, 2012
 Buku Teks SO
A concise guide to statistics
Hans Michael Kaltenbach
[Springer , ], 2012
 eBooks
Hayes, Denis
The Official earth day guide to planet repair
Island Press, 2000
 Buku Teks