Q:

How to add reference to other project in ASP.NET 5 Preview?

In a Visual Studio 2015 solution I have a folder structure as follows:
 -src
    -Project.Models
       (...)
       -MyModel.cs
    -Project.Web
       (...)
       -Controllers
         -MyControllers.cs
       -Dependencies
       -project.json

Where Project.Web is a ASP.NET 5 Web API project and Project.Models a ASP.NET 5 Class Library.
Now I want to use MyModel of Project.Models in MyController of Project.Web. To do this I need to reference the Models project from the Web project. I cannot get this to work here. The using Project.Models statement keeps highlighting the Models part in red because the assembly reference cannot be found.

What I tried:

The usual "Add reference" in combination with using statement
Creating a NuGet package of Project.Models (by specifying "Compile on built" in properties), adding the NuGet package to a local repository and referencing it in project.json.

Both things do not seem to work also after restarting Visual Studio.
Can someone explain to me how to accomplish referencing the Project.Models from Project.Web?
/Edit Include project.json:
{
  "webroot": "wwwroot",
  "version": "1.0.0-*",

  "dependencies": {
    "Microsoft.AspNet.Mvc": "6.0.0-beta5",
    "Microsoft.AspNet.Server.IIS": "1.0.0-beta5",
    "Microsoft.AspNet.Server.WebListener": "1.0.0-beta5",
    "Microsoft.AspNet.StaticFiles": "1.0.0-beta5",
    "Microsoft.AspNet.Loader.IIS": "1.0.0-beta5",
    "Microsoft.AspNet.Loader.IIS.Interop": "1.0.0-beta5",
    "Microsoft.Framework.Runtime": "1.0.0-beta5",
    "Microsoft.AspNet.Mvc.Xml": "6.0.0-beta5",
    "MongoDB.Driver": "2.0.1"
  },

  "commands": {
    "web": "Microsoft.AspNet.Hosting --config hosting.ini"
  },

  "frameworks": {
    "dnx451": { }
  },

  "exclude": [
    "wwwroot",
    "node_modules",
    "bower_components"
  ],
  "publishExclude": [
    "node_modules",
    "bower_components",
    "**.xproj",
    "**.user",
    "**.vspscc"
  ]
}

And global.json
{
    "projects": [ "src", "test" ],
    "sdk": {
        "version": "1.0.0-beta5",
        "runtime": "coreclr",
        "architecture": "x86"
    }
}

A:

The problem was that I was using .NET Core. When I changed my frameworks entry in the project.json file to use
"dnx451": { }

instead of 
"dnxcore50": { }

the references were included again (the red of the image became black). Seems like .NET core does not (yet?) support all packages.

