Personal journal
Twain, Mark. Mark Twain's Notebook, edited by Albert Bigelow Paine. The Mark Twain Company, 1932, ch. 25. Originally from Notebook, c. 1896.
Da Vinci, Leonardo. The Notebooks of Leonardo da Vinci. c. 1883.
Darwin, Charles. "Notebook B." Transmutation of Species. 1837-1838, p. 231.
Darwin, Charles. "Transmutation of Species: Notebook B [1837-1838]." Charles Darwin's Notebooks, 1836–1844, transcribed and edited by David Kohn. Cambridge University Press, 2009.
Kierkegaard, Soren. Journal entry. c. 1848.
Kierkegaard, Soren. The Journals of Kierkegaard, translated by Alexander Dru. Harper Torch, 1959.
Thoreau, Henry David. Journal entry. 25 July 1839.
Thoreau, Henry David. The Heart of Thoreau's Journals, edited by Odell Shepard. Dover Publications, 1961.
Twain, Mark. "Extracts from Adam's Diary: Translated from the Original Ms." The Niagara Book. Buffalo: Underhill and Nichols, 1893.
Twain, Mark. "Extracts from Adam's Diary." The Best Short Stories of Mark Twain, edited by Lawrence Berkove. Modern Library, 2004.
Aurelius, Marcus. Meditations. c. 180, bk. 4.
Aurelius, Marcus. Meditations, edited and translated by Martin Hammond. Penguin Classics, 2015, bk. 4.
Lincoln, Abraham. Fragment written by Abraham Lincoln but found after his death by John Hay. c. 2 Sept. 1862?
Lincoln, Abraham. "Meditation on the Divine Wall, c. early September 1862." Abraham Lincoln: Speeches and Writings 1859-1865, edited by Don E. Fehrenbacher. Library of America, 1989.
Thoreau, Henry David. Journal entry. Nov. 1850.
Thoreau, Henry David. The Journal of Henry David Thoreau, 1837-1861, edited by Damion Searls. New York Review of Books, 2009, pt. 2.
Twain, Mark. Mark Twain's Notebook, edited by Albert Bigelow Paine. The Mark Twain Company, 1932, ch. 20. Originally from Notebook, c. 1888.
Thoreau, Henry David. Journal entry. 23 Aug. 1853.
Thoreau, Henry David. The Heart of Thoreau's Journals, edited by Odell Shepard. Dover Publications, 1961.
Twain, Mark. Mark Twain's Notebook, edited by Albert Bigelow Paine. The Mark Twain Company, 1932, ch. 35. Originally from Notebook, c. 1904.
Lincoln, Abraham. "Definition of Democracy." 1 Aug. 1858?
Lincoln, Abraham. "On Slavery and Democracy, 1858?" Abraham Lincoln: Speeches and Writings 1832-1858, edited by Don E. Fehrenbacher. Library of America, 1989.
Fitzgerald, F. Scott. "Notebook O: Observations." The Crack-Up, edited by Edmund Wilson. New Directions, 2009. Originally published in Notebook O, c. 1940.
In reference to James Mill, the father of John Stuart Mill.
Bentham, Jeremy. Quoted in Memories of Old Friends, being Extracts from the Journals and Letters of Caroline Fox, edited by H. N. Pym. Philadelphia: J. B. Lippincott & Company, 1882. Originally written as a journal entry dated 7 Aug. 1849.
Emerson, Ralph Waldo. Journal entry. 31 Aug. 1838.
Voltaire. The Piccini Notebooks. c. 1738-1750.