Gyrokinetic theory
Start with Howe et al. (2006). Appendix A is particularly useful. You may wish to read this in conjuction with Abel et al. (2013).
You may find in your reading that authors use the fields \(\delta A_\parallel\) and \(\delta B_\parallel\) for the magnetic field, this is because...
In gyrokinetic theory it's common to use the Coulomb gauge \(\nabla \cdot \mathbf{A} = 0\) whereas in MHD theory you sometimes use...
Contributed by: Bailey Cook