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To install itextsharp.xtra from the command line, run the following command:
nuget install itextsharp.xtra -Version 5.4.2 -Source https://nuget.sapec.md/nuget/Sapec/
To install itextsharp.xtra from the Package Manager Console within Visual Studio, run the following command:
Install-Package itextsharp.xtra -Version 5.4.2 -Source https://nuget.sapec.md/nuget/Sapec/
For projects that support PackageReference, copy this XML node into the project file to reference the package.
<PackageReference Include="itextsharp.xtra" Version="5.4.2" />