Example of pulling volume data URL?

As stated in a previous post, my app recently started suffering an issue where it no longer pulls volume data correctly - basically I don't get any results returned.

Can someone let me know the correct syntax for querying the API for volume data?

Thanks,

Lewwy.

Edit: I was using this until it randomly stopped working a few weeks ago: http://www.comicvine.com/api/volume/42721/?api_key=MY_KEY&format=xml

With help from forum member @matthewlupo I learned you need to pass the resource ID, so for anyone else who might be struggling..

http://www.comicvine.com/api/volume/4050-SERIES_ID/?api_key=YOUR_API_KEY&format=xml