   # * `keywords` - an array of keywords (eg `['constant', 'boltzmann constant']`)
   # * `authors` - an `Collection` of `User`s that are attributed as authors
   return BaseModel.extend
+    # This is a "loading" promise (result of 1st fetch)
+    # TODO: use a private instance variable once this class becomes a coffeescript class
+    _loading: null
+
     mediaType: 'application/vnd.org.cnx.module'
     accept: []
     loaded: false

      # Default language for new content is the browser's language
      language: navigator?.language or navigator?.userLanguage or 'en'

    # Begin editing this medium as soon as it is added
    addAction: () ->
      id = @id or @cid

        view = new View({model: @})
        callback(view)

        @load()

    # Change the toolbar view when editing this
    toolbarView: (callback) ->
