James H. Bramble, Tzanio V. Kolev
, Joseph E. Pasciak:
The approximation of the Maxwell eigenvalue problem using a least-squares method. Math. Comput. 74(252): 1575-1598 (2005)

The approximation of the Maxwell eigenvalue problem using a least-squares method. Math. Comput. 74(252): 1575-1598 (2005)