Harmonic Superfields in N=4 Supersymmetric Quantum Mechanics
  This is a brief survey of applications of the harmonic superspace methods to the models of N=4 supersymmetric quantum mechanics (SQM). The main focus is on a recent progress in constructing SQM models with couplings to the background non-Abelian gauge fields. Besides reviewing and systemizing the relevant results, we present some new examples and make clarifying comments. 
Evgeny A. Ivanov
hep-th