Kubar's sketch shows the traditional fixed blade version - I would like to eventually own one, but they are rare and expensive as antiques. Still made today tho.
Meanwhile, the 'real' folding versions are fairly well available, and all have basically the same general shape, a narrowish single edged spearpoint blade designed for thrusting, and the reduction in grip area just behind the bolster. they come in diffeent sizes, grip scale materials, and can be locking or not.
The french Laguiole style style usually has a long clipped spine single edge, also can be locking or non-locking, note NO notch.
Found a Mythical (
) Corsican knife maker that combines the best of both the fixed style and is folding (back-lock), not an antique tho. They also make the fixed blade stylus versions, just a whole lot more expensive. Mine: approx. 20.5 cm. open, 100 gm, 440C, hand made, each is unique.