Template:OldStyleDate/doc

Usage
This template is used for displaying a date in both Old Style and New Style, including a discreet link to the article Old Style and New Style dates, in cases where the year is the same in both Styles.

NS day and month year

If it helps you remember the order of the parameters, you may optionally choose to think of it like this:

NS day and month NS year

Note that in this usage the fourth parameter will be ignored when the template is rendered.