Hello!

I have a book that says

My first question is, how are they defining their cartesian components for a third order tensor?Define the 9 Cartesian components of a second order Tensor T by .

In component form, this can be written as .

This can be generalised for higher order tensors. For example, if B is a tensor of order 3 then .

Is there a general rule for defining cartesian components in a k-th order tensor?

Thankyou to anyone who posts!