Arkansas' is correct. For singular proper names ending in S, use only an apostrophe: Achilles' heel. #ACESchat https://t.co/8yqGadgLl2— APStylebook (@APStylebook) July 13, 2016
Arkansas' is correct. For singular proper names ending in S, use only an apostrophe: Achilles' heel. #ACESchat https://t.co/8yqGadgLl2