Another Dylan song that Dylan didn't release - the first official release of I'll Keep It With Mine was a rather splendid, and surprisingly jaunty version by Judy Collins, released in 1965:

Audio: m4a

The version we're more familiar with was by Nico recorded for her first solo album Chelsea Girl:

Nico - I'll Keep it With Mine

In an interview for AV Club however Dean suggested that their cover owed more to the version by Paisley Underground supergroup Rainy Day.

We kind of like the version by Rainy Day, which was this supergroup featuring David Roback, Kendra Smith, Susanna Hoffs, a Paisley Underground thing. That’s kind of what we based that on.
Rainy Day - I'll Keep it With Mine

But this is my favourite version by Fairport Convention featuring the wonderful Sandy Denny in 1969

Fairport Convention - I'll Keep it With Mine

Dean & Britta recorded it for Nico's screen test in 13 Most Beautiful and it has been released on the accompanying album and a couple of 7" singles - all CD and vinyl releases feature one of two remixes by the late Scott Hardkiss - but Britta allowed this site to share the unremixed version.

Dean & Britta - I'll Keep It With Mine (Scott Hardkiss acoustic remix)
Dean & Britta - I'll Keep It With Mine (Scott Hardkiss electric remix)

See all posts in the Originals series