Actually, both are special cases of a norm that raises the absolute values of the matrix components to a certain power e. If this exponent e becomes large, then: (mainly the diagonal elements of the matrices in the denominator assume 1) where #p denotes the number of perfect matches (similarity value of 1.0) between words of the two documents and n (m) is the number of words in text t (u).
with an increasing exponent, sn L e,1 tends to focus on very good matches and disregards the others.