Forms :: Sorting Combobox Displayed Value

I have a combobox which lets you select from a list of pseudonyms. Each pseud belongs to an author; authors can have multiple pseudonyms and exactly one main pseudonym. This is the table structure (picture of relationships attached below):

Code:
tblStory: StoryID (PK), AuthorID (FK), Title, etc.
tblAuthor: AuthorID (composite PK, autonumber), MainPseudID (composite PK)
tblPseud: PseudID (PK, autonumber), Pseud, AuthorID (FK)

The combobox list shows all the pseudonyms and then stores the corresponding AuthorID. At the moment, the pseudonym displayed in the combobox (once a selection has been made) is simply the first alphabetically for that particular author: for instance, if a story has AuthorID = 5, and Author 5 goes by anon, anonymous, and unknown, the combobox for that story will display "anon".

How can I make the main pseudonym (tblAuthor.MainPseudID = tblPseud.PseudID) be displayed instead?

Control source is tblStory.AuthorID

Row source:

Code:
SELECT tblPseud.AuthorID, tblPseud.Pseud, tblAuthor.MainPseudID
FROM (tblAuthor LEFT JOIN tblPseud ON tblAuthor.AuthorID = tblPseud.AuthorID)
LEFT JOIN tblStory ON tblAuthor.AuthorID = tblStory.AuthorID
ORDER BY tblPseud.Pseud;