Hyperelastic+ Damage with UMAT - Abaqus/Standard

 Hello,

 I have the following problem:

I want to implement a hyperelastic material model with a damage function (like the pseudo-elasticity of Ogden) by using a UMAT in Abaqus/Standard.

For this, in the first step I try to implement the damage of Ogden, which already exist in Abaqus/Standard.

But I don't know in which way I build the tangent stiffness matrix for this case (nonlinear and dependent of the history)

Do anywhere know a good literature in order to read and understand this issue?

Ideally anywhere have a such numerical formulation what I can take over.

Thank you in advance

Ahmetoglu