Limit flickr JSON image number?

I tried this URL and it works fine...

http://api.flickr.com/serv开发者_开发知识库ices/feeds/photos_public.gne?per_page=6&jsoncallback=?

...almost. It is set to "per_page=6" but it don't listen to it. What's wrong?

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You have an extra question mark at the end. Can you remove the last parameter?

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It seems like this URL does not accept any limit.

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Unfortunately according to the API this isn't supported

http://www.flickr.com/services/feeds/docs/groups_pool/

I was in need of it as well