Esther M. Zimmer Lederberg to François Jacob
Maleness Transferred by Infection at High Frequency
January 12, 1961
Joshua Lederberg is well-known for his work in discovering
microbial sexuality (Nobel Prize, 1958). However, Esther
Lederberg discovered and named the Fertility Factor "F",
by which microbial sexual differentiation (maleness) may
be conferred via phage infection, as stated in the letter
below.