As opposed to sex, which comprises only the biological differences among members of a species, typically observable in the chromosomes and reproductive systems of an organism, gender refers to social and cultural identity based on a set of expectations regarding characteristics, behaviors, and norms. Gender identity refers to an individual's internal sense of their own gender and how they determine they fit into their culture's gender paradigm.
This guide provides links to a variety of sources, including books and e-books, journal articles, databases, and websites, that are helpful in researching different aspects of this impactful topic.
Gender identity -- Social aspects
Human body -- Social aspects