"...", exactly three dots, is the correct form for ellipsis as used in research papers to indicate something has been omitted. "

Or in a quote on a Mudcat post for example, for precisely the same reason. But it also is correctly used, and probably more freequently used, as a way of finishing a remark, and leaving it open to the reader to assume that something more could be said, but...

In "Eats, shoots and leaves", the book about punctuation that just about every pedant in the UK received (and gave) as a present this Christmas, there is quoted a dialogue from Dud and Pete in "Not Only...but also" (talking about Neville Shute's novel A Town Like Alice) which is cheerfully relevant here:

DUD: What happened after that, Pete?
PETE: Well, the bronzed pilot goes up to her and they walk away, and the chapter ends in three dots.
DUD: What do those three dots mean, Pete?
PETE: Well, in Shute's hands, three dots can mean anything.
DUD: How's your father, perhaps?
PETE: When Shute uses three dots it means, "Use your own imagination. Conjuremteh scene up for yourself." (Pause) "Whenever I see three dots I feel all funny.