Given a nested median formula:
$ \operatorname{med}\big( \operatorname{med}(a_{1,1},\ldots,a_{1,n}), \operatorname{med}(a_{2,1},\ldots,a_{2,n}), \ldots, \operatorname{med}(a_{k,1},\ldots,a_{k,n}) \big) $
Is there a rule for simplifying this formula (making it not nested)?