# How to separate Roman numerals for a range of numbers?

Arabic numerals are separated using en-dash:

``````pages 101--123, 2--3 and so on
``````

What is typographically correct way to separate Roman numerals?

For example:

with en-dash

``````in the XIX--XX centuries
``````

with en-dash plus two `\,`

``````in the XIX\,--\,XX centuries
``````

or, maybe, with the usual dash

``````in the XIX\,---\,XX centuries
``````
-
I'd say that you should use (i) en-dashes and (ii) whatever amount of horizontal separation between the (roman) numerals and en-dashes that's appropriate for your country's typographic practice. In the U.S., it's not customary to insert a space (generally a thin-space) between the numerals and the dash, but in some other countries it is customary to do so. – Mico Jan 11 '13 at 19:46
Conceptually, an en-dash is used where 'and' or 'to' is appropriate (at least in the tradition in the UK). Thus a page range with any form of page numbering is an en-dash, as you would read as 'to'. – Joseph Wright Jan 11 '13 at 19:50
@Mico, Joseph Wright: thank you – Physicsworks Jan 11 '13 at 19:53

for a page span, an en-dash (`iv--ix`) would be appropriate. i see no reason why this shouldn't also be appropriate for cap roman numerals for centuries. the en-dash, with no surrounding spaces, traditionally indicates a span in u.s. typography. as mico points out in a comment, the typographic traditions regarding spaces may differ in other countries.