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Start by downloading documents-stack.png and adding the file to the project resources. This image must be built as a resource in order for WPF to use it, so select the image in the Resources folder shown in the Solution Explorer panel of Visual Studio and change the Build actionAction property to Resource.
Now, add a new folder named Ribbon to the plugin project. Inside this folder, create a new WPF user control named VolumeModelRibbon.xaml and adapt the contents (in the designer) as shown below:
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