Models that contain the Modeling Application : GNUstep NeXTStep/OpenStep ()

(GNUstep is a cross-platform, object-oriented framework for desktop application development. Based on the OpenStep specification originally created by NeXT (now Apple), GNUstep enables developers to rapidly build sophisticated software by employing a large library of reusable software components. GNUstep is used in production environments at several organizations.)