NuGet package OxyPlot.Wpf 1.0.0 doesn't include the file OxyPlot.Xps.dll; older versions of OxyPlot.Wpf do.
It seems this file has disappeared from newer versions of the OxyPlot.Wpf nuget-package, while the older versions (the ones with version numbers like 2014.x.y.x, 2015.x.y.z etc.) include it. There is also no separate NuGet package for it.
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