Stein, Lincoln D.
Official guide to programming with CGI.pm
Wiley, 1998
 Buku Teks
Langer, Maria
Quicken 2000 : the official guide
Osborne/McGraw-Hill, 1999
 Buku Referensi
Guide to official statistics
Central Statistical Office
Her Majesty`s Stationery Office, 1986
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Oehler, Karsten
IBM Cognos TM1 : the official guide
McGraw-Hill, 2012
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Hayes, Denis
The Official earth day guide to planet repair
Island Press, 2000
 Buku Teks