Steps to reproduce:
1. Download attached MissingReferenceUtility script. It is based on script found at http://gamasutra.com/blogs/LiorTal/20141208/231690/Finding_Missing_Object_References_in_Unity.php
2. Open Standard Assets project and place the downloaded script to Assets\Editor folder.
3. Utility menu will appear. Either select option "Utility -> Find missing references in assets" or "Utility -> Find missing references in all scenes". Script will report missing references to console. Reports of missing references of current Standard Assets version are attached.

Please consider that each separate Standard Assets package contains even more missing references. For example, FirstPersonRigidbody controller prefab has a reference to DepthOfField script, which becomes missing reference if Effects package is not imported.