
Letter to Thomas Jefferson Hogg (3 January 1811)
Source: Isis Unveiled (1877), Volume I, Chapter XII
Letter to Thomas Jefferson Hogg (3 January 1811)
Source: Against a Scientific Justification of Animal Experiments, p. 340
Lecture at Vassar College, Poughkeepsie, New York (14 May 1921)
Closing lines
The Private Life of Plants (1995)
Source: 1960s, Prisoner's dilemma: A study in conflict and cooperation (1965), p. v
"The Price of the Head", Instauration magazine (March 1980)
1970s, 1980s