Paragraph 3, Line 21 Letters To Atticus: Ad Atticum VI by Cicero
Paragraph 2, Line 4 Letters To Friends: Ad Familiares III by Cicero
Paragraph 15, Line 22 Epistulae Morales Ad Lucilium: Epistulae Morales, Liber VI by Seneca
Section LIV. Seneca Lucilio Suo Salutem, Paragraph 1, Line 3