How to use ember data "sub-models" when using pods

Question

I have a json like this:

{
    id: 'some-id',
    username: 'myusername',
    name: {
       first: 'first-name',
       last: 'last-name'
    }
}

I'm using pods with the following structure:

pods/
    user/
        model.js
        serializer.js
        name/
            model.js

With user/model.js:

import DS from 'ember-data';

export default DS.Model.extend({
    username: DS.attr('string'),
    name: DS.belongsTo('?????????????', { async: false })
});

With user/name/model.js:

import DS from 'ember-data';

export default DS.Model.extend({
    first: DS.attr('string'),
    last: DS.attr('string')
});

With user/serializer.js:

import DS from 'ember-data';

export default DS.RESTSerializer.extend(DS.EmbeddedRecordsMixin, {
    attrs: {
        name: { embedded: 'always' }
    }
});

My question is how do I refer the user/name/model in the belongsTo relation of user/model?