The fourth and latter arguments of AGGREGATE() have the same summary: the cells of the range which are to be taken into account or mandatory 2nd argument for certain functions. And, m-th (m>=4) argument is named "Reference 2..n or k (m-3)." But what might be "mandatory 2nd argument" is only the fourth. So, the fourth argument can be "Reference 2 or k". The m-th (m>=5) can be "Reference (m-2)" or "Reference 3..n (m-4)."
@Eike, I thought you might be interested in this...
The problem is, the argument of the 4th, 6th, ... parameter depends on the function selected with the 1st argument. While for AVERAGE(), COUNT(), ... each argument is an independent cell range reference or array, for the LARGE(), SMALL(), ... functions every second argument is a number or array (or reference of course) that determines the operation of the function on the previous argument and for those functions is mandatory. However, I agree the wording "Reference 2..n or k3" and so on is slightly confusing (fwiw, I don't see any "(m-3)" or such there), but I don't have any better atm. Further problem is, the numbers are generated and there is no distinction whether it should be "Reference 2, Reference 3, ..." or "Reference 2, k2, Reference 3, k3, ...", the dialog does not know, it has to be a string that can be applied to all parameters.
(In reply to Eike Rathke from comment #2) > for the > LARGE(), SMALL(), ... functions every second argument is a number or array > (or reference of course) that determines the operation of the function on > the previous argument and for those functions is mandatory. These functions accept only a single pair. Two types of usages are; AGGREGATE(Function, Option, Reference 1, Reference 2, Reference 3,...) and AGGREGATE(Function, Option, Array, k). Combining them, AGGREGATE(Function, Option, Reference 1 or array, Reference 2 or k, Reference 3..n 1, Reference 3..n 2,...) should be fine.