Kinsey, Alfred C., B. Pomeroy Wardel, E. Martin Clyde, & Gebhard Paul; The Sexual Behavior of the Human Female; 888 pp
Kinsey c.s.' book "The Sexual Behavior of the Human Female", 1953, is given here as a long pdf file.
Kinsey, Alfred C., Pomeroy Wardel B., & Martin Clyde E.; Kinsey - The Sexual Behavior of the Human Male; 819 pp.
Here is given the text of the book "Sexual behavior in the Human Male", Kinsey c.s., 1948, in a long PDF file.
Kinsey, Alfred; Sexual Behavior in the Human Male (1948) - chapter 5 - Early Sexual Growth and Activity; 35 pp, 157 - 192
Chapter five, here presented as a .PDF file, is devoted to early sexual growth and activity and first sets out to define erotic arousal and orgasm, noting the variation in pattern of orgastic response in individuals.
One significant finding was that more than 99% of these boys adopted a regular routine of sexual activity after the initial experience of ejaculation.