Two single crystals were grown by using the strain-anneal technique. Three rectangular parallelepiped samples were cut from these crystals with the long dimension directed along one of the hexagonal axes. These are designated as the <1120> a-axis, the <1oTo> b-axis, and the <0001 > c-axis.
Jew, Terry Ting and Legvold, S., "Magnetic anisotropy in dysprosium single crystals" (1963). Ames Laboratory Technical Reports. 63.