This page contains the link to the interview of Danielle Cozart-Steele, who organized the Transgender Singing Voice Conference, a conference first started in 2017 and occurs every two years. You can view a transcript of the interview here.
While Cozart-Steele was a choir teacher at Earlham College, she encountered a transitioning student who wanted to change vocal parts, moving from bass to alto. When researching on how to best train this student, she encountered no literature on working with transgender people on vocal performance. She reached out to other instructors and interested researchers and started the Transgender Singing Voice Conference.
This interview touches on the topics of voice instruction and vocal performance, allyship, inclusivity, and male to female transition.
More materials related to the Transgender Singing Voice Conference (at least for 2017 and 2019 conferences) is located in the archives at Earlham College.