Causa, M. T.; Fainstein, C.; Nieva, G.; Sanchez, R.; Steren, L. B.; Tovar, M. et al. Crystal Field Interaction and Magnetic Order in GdBa/sub 2/Cu/sub 3/O/sub 7/, article, January 1, 1988; (https://digital.library.unt.edu/ark:/67531/metadc1092705/m1/1/: accessed July 16, 2024), University of North Texas Libraries, UNT Digital Library, digital.library.unt.edu; .