Language for subpoena from cloud services

Have any of you successfully subpoened data from cloud providers? We have a situation where the subjects of my investigation tried to delete data from Carbonite, Dropbox, and Google Drive. I'm working on getting the login credentials to see what's still there, but I'd also like to send a subpoena to them for the data or at least for the preservation of the data.

I'd really appreciate any sample language for such a subpoena or letter.

Thanks.