What is the possessive of Odysseus Odysseus' or Odysseus's?

The possessive form of "Odysseus" can be written as either "Odysseus'" or "Odysseus's," depending on the style guide being followed. The first form, "Odysseus'," is the preferred form in some style guides, especially when the Word ends in an "s" sound. The second form, "Odysseus's," is also widely accepted and used, particularly in American English. Both forms are grammatically correct, so it ultimately comes down to personal preference or adherence to a specific style guide.