Higher-order corrections to electron-scattering multipoles
  A procedure is suggested for calculating electro-excitation multipoles to order $1/M^{2}_{N}$ with only the operators required in the calculations to order $1/M_{N}$. It is also shown that calculations to order $1/M^{2}_{N}$ cannot account for the contributions of a fully relativistic calculation of the transverse response. 
J. Grineviciute and Dean Halderson
nucl-th