Ah, international phone numbers. A subject near and dear. My last job
entailed lots of travel to many countries, so trying to keep the phone
numbers (and access codes) straight was enough to drive one batty. My
*personal* notation for phone numbers - what I use when I'm jotting
'em into my address book - is along the lines of +1 (1)415 626.3645,
where +1 is the country code, and (1) is the in-country access code.
This isn't really acceptable for general typesetting since that extra
parenthetical bit can be confusing. In this case I use a simplified
+1 415 626.3645
This provides white space to separate the number into it's logical
pieces, flags the country code with the `+' (which seems to be the
default standard), and allows the phone number to be formatted along
the lines of local custom by using `.' to denote the constituent bits.