https://collaborate.princeton.edu/en/publications/crystal-field-interaction-in-the-pyrochlore-magnet-hosub2subtisub/
Crystal-field interaction in the pyrochlore magnet Ho2Ti2O7 - Princeton University
in thecrystalfieldinteractionmagnet
https://impact.ornl.gov/en/publications/spin-correlations-in-hosub2subtisub2subosub7sub-a-dipolar-spin-ic/
Spin correlations in Ho2Ti2O7: A dipolar spin ice system - Oak Ridge National Laboratory