1. Departamento de Física EPS Universidad de Burgos Burgos Spain
2. Hawaii Institute of Geophysics and Planetology SOEST University of Hawaii at Manoa Honolulu HI USA
3. Laboratorio Interinstitucional de Magnetismo Natural Instituto de Geofísica Unidad Michoacán UNAM Morelia Mexico
4. Institute of Geology of Ore Deposits Petrography Mineralogy and Geochemistry—Russian Academy of Sciences (IGEM RAS) Moscow Russia
5. Alexandre Janelidze Institute of Geology—Ivane Javakhishvili Tbilisi State University Tbilisi Georgia