I submit that there is no such language in any of our policies. If there is, then whoever wrote it has no clue what we meant when we were discussing tertiary sources many years ago. Tertiary sources are just summaries of notable secondary sources. So they quite obviously provide notability, in fact perhaps the ultimate form of it, trouncing secondaries quite roundly, since they in-fact pick the most notable topics to report out of those!
Will Johnson
In a message dated 8/19/2009 2:16:36 AM Pacific Daylight Time, surreptitious.wikipedian@googlemail.com writes:
The thrust of the argument against tertiary sources is this: "Third party sources don't provide any evidence of notability unless they contain some sort of commentary on their subject matter, othewise they are classed as tertiary sources."