On top is the early De Rosa logo that I refer to.  I don't know when its use began, or when it ended for that matter, but I'm pretty sure it was in use all through the 70's and possibly into the very early 80's..

And below the logo is the De Rosa name in a font and design which I believe remains unchanged till today.

My thanks to Mark Bulgier for the graphic, which I downloaded from his invaluable collection of cycling catalogs, located at http://www.bulgier.net/pics/bike/Catalogs