     courseId: React.PropTypes.string.isRequired
   contextTypes:
     router: React.PropTypes.func
-  mixins: [BookContentMixin]
+  mixins: [BookContentMixin, GetPositionMixin]
 
   getCNXId: ->
     @props.cnxId or @context.router.getCurrentParams().cnxId

      <i className='fa fa-chevron-right'/>
    </Router.Link>

  render: ->
    {courseId} = @context.router.getCurrentParams()
    # read the id from props, or failing that the url

Router = require 'react-router'
BS = require 'react-bootstrap'
_  = require 'underscore'
$ = require 'jquery'

HTML = require '../html'
ArbitraryHtmlAndMath = require '../html'
BookContentMixin = require '../book-content-mixin'
GetPositionMixin = require '../get-position-mixin'

{ReferenceBookPageStore} = require '../../flux/reference-book-page'
{ReferenceBookStore} = require '../../flux/reference-book'
