Mariano is giving us a Microsoft Dynamics GP 2015 Developer’s Preview: .NET Framework Interoperability
The Dynamics GP Blogster: Microsoft Dynamics GP 2015 Developer’s Preview: .NET Framework Interoperability
Development & IntegrationMicrosoft & the GP EcosystemGP 2015
Archived post from 2014. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.