Elderly Asian gentleman

This is probably my most ambitious project to date.
The ref can be found here [link]
About 45 hours,

Materials:
A4 smooth Bristol.
2b mechanical,3b,5b,9b woodcased.

techniques used :
a grid, blending, alot of blending, stipling, reverse stipling, hatching, circlism and indentations.

Thanks to for letting me use the ref.

As always comments and crits are welcome