Group blog filtered on author

Often I'm only interested in postings by _one_ author on a Group Blog. So here you can enter a Blog url (or the Feed url, whichever you prefer) and (part of) the author's name to get the Group Blog feed filtered on your favourite author. It works both on RSS (item.author) and Atom (item.dc:creator) Feeds. The example giving is the Dutch blog FrankWatching.com (and its original author Frank)