In prose, use month names (i.e. 1st Jan 1979, or Jan 1st 1970). Where numbers must be used for some reason use four-digit-year first if you can. If you can't use the dictated standard or, if there isn't one (raising the obvious question of why that would be), go with the form that will be familiar to most of your readers.

In other words, as with all things, prefer unambiguous forms but consider and respect your audience.