[clean-list] uniqueness error

[valery at freesurf.fr]

> You can try replacing # with #! or else you'll have to chain s through
> the various functions with the array-selection method with ! as
> explained on page 53 of the CleanLangRef manual on the Clean site:

Where is this CleanLangRef ?
Google doesn't find it. Maybe you meant CleanLangRep, but then page 53 is
the wrong place.

-- Valery