[seqfan] Changing References to Links

[David Scambler]

What is the etiquette for changing a reference to a link when you 
notice that the article is on the web?

For example. In sequences A091869, A092107, A098747

Y. Sun, The statistic "number of udu's" in Dyck paths, 
Discrete Math., 237 (2004), 177-186.

is available at http://www.combinatorics.cn/publications/papers/2004/udu.pdf

Thanks
dave