Benjamin Franklin, William-Temple Franklin (1818). “Memoirs of the Life and Writings of (the Same), Continued to the Time of His Death by William Temple Franklin. - London, H. Colburn 1818”, p.2
Gary Miles Chassman, Smithsonian Institution. Traveling Exhibition Service, Martin Luther King, Jr. Center for Nonviolent Social Change (2002). “In the Spirit of Martin: The Living Legacy of Dr. Martin Luther King, Jr”
Epictetus, Marcus Aurelius, Lucius Annaeus Seneca (2016). “Stoic Six Pack: Meditations of Marcus Aurelius, Golden Sayings, Fragments and Discourses of Epictetus, Letters from a Stoic and The Enchiridion”, p.92, Enhanced Media Publishing