On May 7th, 1933 the Nazi students raided the Institute for Sexual Research, an early human sexual research institute that included support for the transgender community and the first working male to female surgery made famous by the Danish Girl.

3 days later they burned the Institute's books and research as part of the Nazis first mass book burning that also included works of others they labeled undesirables

Amongst the works was the work of Jewish poet, Heinrich Heine, including the line he wrote in 1821:
Where they burn books, they will, in the end, burn human beings too.

https://timesmachine.nytimes.com/timesmachine/1933/05/07/issue.html

https://en.wikipedia.org/wiki/Institut_f%C3%BCr_Sexualwissenschaft

https://www.ushmm.org/collections/bibliography/1933-book-burnings

https://web.archive.org/web/20150803154601/http://www.lgbthistorymonth.org.uk/history/lilielbe.htm