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+The default Z3 bindings for .NET are built for the .NET framework version 4.
+Should the need arise, it is also possible to build them for .NET 3.5; the
+instructions are as follows:
+
+In the project properties of Microsoft.Z3.csproj:
+- Under 'Application': Change Target framework to .NET Framework 3.5
+- Under 'Build': Add FRAMEWORK_LT_4 to the condidional compilation symbols
+- Remove the reference to System.Numerics
+- Install the NuGet Package "Microsoft Code Contracts for Net3.5"