This is a body of research going back to at least 2008, usually referred to
in the literature as "Cortina’s theory of selective incivility". It
categorizes types of selective incivility, and has data showing that
selective incivility causes marginalized groups to leave organizations.
"That is, 'generally' uncivil words and deeds make no overt reference to
gender or race (or any other social dimension). Nevertheless, incivility
may sometimes represent a covert manifestation of gender and racial bias
when women and people of color are selectively targeted."
The most frequently cited study is Selective Incivility as Modern
Discrimination in Organizations (2013):
http://journals.sagepub.com/doi/abs/10.1177/0149206311418835