English literature: starting research and putting a plan for my dissertation

hi
i am a student of English literature and i have already chosen a theme to my dissertation. it is dualism in Hemingway's presentation of female characters: a selection of his late writings

can you advice me what are the best novels for this theme and how to deal with
i will be so grateful for your help and guidance

Well, it depends on how you are using the concept "dualism."

I want to advise you to choose the book that interests you the most. It is not a good idea to advise you to look at a particular book in order to write about that concept. The best idea is to forget the theme and look at HIS themes.

Again, FORGET YOUR THEME. Your theme will stop you from making progress. Go take a trip on a bus or train, and bring with you a Hemingway novel and a notebook for note taking. Treat yourself to an awesome experience with his work.

Only after having that awesome experience will you have something worth sharing. All you need is one good experience, and then the paper will write itself.