Freud, S., Abraham, K., Abraham, H. C., & Freud, E. L. (1965). A psycho-analytic dialogue: The letters of Sigmund Freud and Karl Abraham, 1907-1926. Hogarth Press.

Freud, Sigmund, Karl Abraham, Hilda C. Abraham, and Ernst L. Freud. A Psycho-analytic Dialogue: The Letters of Sigmund Freud and Karl Abraham, 1907-1926. London: Hogarth Press, 1965.

Freud, Sigmund, et al. A Psycho-analytic Dialogue: The Letters of Sigmund Freud and Karl Abraham, 1907-1926. Hogarth Press, 1965.