Realization of a flux-flow DC-transformer using high temperature superconductors S. Berger, K. Bouzéhouane, D. Crété and J.-P. Contour Eur. Phys. J. AP, 6 2 (1999) 111-113 Published online: 15 May 1999 DOI: 10.1051/epjap:1999159