Well one say it on the inside bell so the chances are good.
Quite the opposite. The Italians wrote things like that to try and pretend they were the real thing. The real ones don't need to pretend. So if somebody writes Constantinople in pen under the bell it probably isn't. Probably in the statistical sense. Drumaholic may know of an instance where Constantinople is written under a genuine one, and if he has such info in his records hopefully he will speak up.
The other obvious Italian feature is the lathing style visible in the photos of the top. Drumaholic may know more specific reasons why it is Italian, but those are the two features I know about. The hammering style is also characteristic of these when combined with that lathing, but as I haven't had lots of these to examine I don't know how generally true this is. But I do always try to give some reasons why a particular conclusion is reached so that we can all gain value.
Below is an annotated pic of what I'm looking at with the lathing, but in words it is that instead of one continuous band across the bow: the lathing looks like it is stepped in maybe 1" sections. I've annotated those places with blue arrows (not always perfectly at the transitions). Hopefully you can see what I mean. Let me know if you need a better picture.
[img]http://black.net.nz/cym2014/Italian-lathing-style.jpg[/img]
Note: I foolishly put the text explaining this in blue as well and it isn't easy to read. Oops.
** EDIT ** I found the other annotated pic of the Italian lathing style I had done previously. Clearer demonstration I think:
[img]http://black.net.nz/cym2014/ItalianLathing.jpg[/img]
Note that this second one doesn't have obvious larger hammering marks like the one you originally posted. They may be there but more subtle, or it is just a different style. There are different styles across the different Italian manufacturers, as well as within one manufacturer. I don't know what they mean, just that the variations exist.