Critical Intersex by Morgan Holmes is not cheap, but it’s a recommended read.
From the publishers’ description:
To date, intersex studies has not received the scholarly attention it deserves as research in this area has been centred around certain key questions, scholars and geographical regions. Exploring previously neglected territories, this book broadens the scope of intersex studies, whilst adopting perspectives that turn the gaze of the liberal, humanist, scientific outlook upon itself, in order to reconfigure debates about rights, autonomy and subjectivity, and challenges the accepted paradigms of intersex identity politics.
The collection is edited by Morgan Holmes, Associate Professor of Sociology at Wilfrid Laurier University, Canada. The book is in print and as an e-book, including from Amazon.com.