I've found this link, which shows you how to obtain the ISSN for any magazine. As I'm currently travelling, that's the best I can do for now – but actually it's probably better than a list, which I might misstype and which will undoubtedly soon become out of date.
Many, but not all, magazines also give the ISSN on the first or large page along with things such as their registered address and copyright information. (You'll need to look at a copy to check the title your story was published under.)
If you're wondering what an ISSN is, or why you'd need one, take a look at these posts.
As I don't have a womag with me to illustrate this pst, I'm using a few pictures from our trip. If you'd like to see more, take a look at my other blog, or on Facebook.