You can analyze Deaf Art pieces and Deaf Theatre performances as primary sources and then look for articles or books for theories, interpretations, etc. of the work.
Explore the Deaf Art, Deaf Artists, and Deaf Theatre websites for some examples.
Australia Sign Language Poet
Walter Kadiki
Brazilian Sign Language Poet
Fernanda de Araugo Machado.
Performers (Brazil): Rosana Grasse, Renata Heinzelmann, Carolina Hessel, Rosani Suzin, Carlos Alberto Goes, Marlene Prado, Silas Queiroz