[Haskell-cafe] howto tuple fold to do n-ary cross product?

[Larry Evans]

http://www.muitovar.com/monad/moncow.xhtml#list

contains a cross function which calculates the cross product
of two lists.  That attached does the same but then
used cross on 3 lists.  Naturally, I thought use of
fold could generalize that to n lists; however,
I'm getting error:

{-- cut here
Compilation started at Sun Nov 23 13:15:24

make
runghc -XMultiParamTypeClasses -XFunctionalDependencies 
-XFlexibleInstances cross.hs

cross.hs:23:30:
     Occurs check: cannot construct the infinite type: a = (a, a)
       Expected type: [a] -> [a] -> [a]
       Inferred type: [a] -> [a] -> [(a, a)]
     In the first argument of `Data.Foldable.foldl1', namely `cross'
     In the first argument of `print', namely
         `(Data.Foldable.foldl1 cross (list2, list3, list1))'
make: *** [run] Error 1

}-- cut here

How do I apply fold to cross and n lists, for n>=0?

TIA.

-regards,
Larry
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