males, including men with boys. Ellis wrote the first objective study of homosexuality (the term was coined by Karl-Maria Kertbeny), as he did not characterize it as a disease, immoral, or a crime. The work assumes that same-sex love transcended age taboos as well as gender taboos. Seven of his twenty-one case studies are of inter-generational relationships. He also developed other important psychological concepts, such as autoerotism and narcissism, both of which were later developed further by Sigmund Freud. Ellis pioneered transgender phenomena alongside the German Magnus Hirschfeld. He established it as new category that was separate and distinct from homosexuality. Aware of Hirschfeld's studies of transvestism, but disagreeing with his terminology, in 1913 Ellis proposed the term sexo-aesthetic inversion to describe the phenomenon. In 1908, the first scholarly journal of the field, Journal of Sexology (Zeitschrift für Sexualwissenschaft), began publication and was published monthly for one year. Those issues contained articles by Freud, Alfred Adler, and Wilhelm Stekel. In 1913, the first academic association was founded: the Society for Sexology. Freud developed a theory of sexuality. These stages of development include: Oral, Anal, Phallic, Latency and Genital. These stages run from infancy to puberty and onwards. based on his studies of his clients, between the late 19th and early 20th centuries. Wilhelm Reich and Otto Gross were disciples of Freud, but rejected his theories because of their emphasis on the role of sexuality in the revolutionary struggle for the emancipation of mankind. Pre-Nazi Germany, under the sexually liberal Napoleonic code, organized and resisted the anti-sexual, Victorian cultural influences. The momentum from those groups led them to coordinate sex research across traditional academic disciplines, bringing Germany to the leadership of sexology. Physician Magnus Hirschfeld was an outspoken advocate for sexual minorities, founding the Scientific Humanitarian Committee, the first advocacy for homosexual and transgender rights. Hirschfeld also set up the first Institut für Sexualwissenschaft (Institute for Sexology) in Berlin in 1919. Its library housed over 20,000 volumes, 35,000 photographs, a large collection of art and other objects. People from around Europe visited the institute to gain a clearer understanding of their sexuality and to be treated for their sexual concerns and dysfunctions. Hirschfeld developed a system which identified numerous actual or hypothetical types of sexual intermediary between heterosexual male and female to represent the potential diversity of human sexuality, and is credited with identifying a group of people that today are