@article {MR4188178,
    AUTHOR = {Feng, Ruyong},
     TITLE = {Difference {G}alois groups under specialization},
   JOURNAL = {Trans. Amer. Math. Soc.},
  FJOURNAL = {Transactions of the American Mathematical Society},
    VOLUME = {374},
      YEAR = {2021},
    NUMBER = {1},
     PAGES = {61--96},
      ISSN = {0002-9947},
   MRCLASS = {12H10 (13B05)},
  MRNUMBER = {4188178},
MRREVIEWER = {Alexander B. Levin},
       DOI = {10.1090/tran/8143},
       URL = {https://doi.org/10.1090/tran/8143},
}