Word document custom properties

[Alan T]

I read from the book:
Microsoft .NEt Development for Microsoft Office at page 82.
The code:

propIndex = "AnotherCustomP roperty";
propValue = "Charles Lutwidge Dodgson";
object[] args = {propIndex. false,
Office.MsoDocPr operties.msoPro pertyTypeString ,
propValue};

I got a error on the parameter on compilation
Office.MsoDocPr operties.msoPro pertyTypeString

I have already included the Word library in the references and also the
using clause.