  We present the basic physical and mathematical ideas (P. Curie, Darboux,
Poincare, Dirac) that led to the concept of magnetic charge, the general
construction of magnetic Laplacians for magnetic monopoles on Riemannian
manifolds, and the results of Yu.A. Kordyukov and the author on the
quasi-classical approximation for the eigensections of these operators.
