: Regardless of the sources you provided (nothing shown at the GoogleBooks link, and a "main albums" list by Allmusic), how is this purported "canonical sequence" aimed at a general audience rather than just fans already familiar with the discography? If there is a source that explicitly says "these are the albums associated with the Who's canon", then it would only be of use here, a section that summarizes an artist's major works (Wikipedia:WikiProject Musicians/Article guidelines). It doesn't spill over to the chronology chain.    

 :: Any arguments as to whether an EP is an "album" or not should be made at WP:ALBUMS. What matters is that there's an article for Tommy (EP) and it's release follows this album. If the EP in question lacks that much notability, nominate it for deletion.