Yeah, it's a series one Moulton. Restoration would be the same as any other old english 3 (or 4) speed. Looks like a strip and repaint or powder coat is in order at this point. I'd expect the rubber suspension blocks to be rock hard by now, so that's the main challenge. I'm sure someone has figured out a replacement.

There's a book on Moultons. I have one somewhere. Moulton club: Moulton Bicycle Club | Moulton Bicycle Club