1. Department
of Physics, Oakland University, Rochester, Michigan 48309, United States
2. Deutsches GeoForschungsZentrum GFZ, Section 4.3, Telegrafenberg, 14473 Potsdam, Germany
3. Institute
of Applied Physics, Academy of Sciences of Moldova, MD 2028 Chisinau, Republic of Moldova
4. Experimental
Physics 5, Center for Electronic Correlations and Magnetism, Institute
of Physics, University of Augsburg, D-86159 Augsburg, Germany