A Portrait Exercise

Hello everyone, here's a little exercise I did! 1 hour sculpting, 1 hour texturing. For the texturing I was aiming for the handpainted look, using a couple of procedurals as a base, and the rest being handpainted. I used the Knife brushes from Substance Painter for the texturing.
Having said that, only the diffuse texture is being used for the final look.

Regarding the concept I used for this exercise, I found it in Pinterest, but for the life of me I cannot find who the artist that created the artwork is.

If by any chance someone sees this and recognizes this from an illustration and knows who the artist of said illustration is, please let me know, I'd like to credit them! Thank you :)