VUMAT implementation of crystal plasticity

[Rcct]

I am new to crystal plasticity simulations and have been studying the concepts from "Introduction to Crystal Plasticity" in Mechanics of Microstructured Materials book. Additionally, I have been going through the publicly available UMAT for crystal plasticity (Huang 1991). I have also come across a paper titled "Comparison of the implicit and explicit finite element methods using crystal plasticity (2007)," where the authors have implemented the model in Abaqus/Explicit environment. Though I now understand the theoretical basis of the crystal plasticity formulation, I have been unable to implement the model as a VUMAT subroutine, as carried out in the paper.

Can anyone share crystal plasticity VUMAT, so that I can study, compare the approaches and work on the model further?