Robert Louis Stevenson, Lloyd Osbourne, Fanny Van de Grift Stevenson (1915). “"Virginibus puerisque," and othe other papers. Memories and portraits. Familiar studies of men and books”
Friedrich Nietzsche, Maudemarie Clark, Brian Leiter (1997). “Nietzsche: Daybreak: Thoughts on the Prejudices of Morality”, p.9, Cambridge University Press