Herbert Hoover, Arnold S. Rice, United States. President (1929-1933 : Hoover) (1971). “Herbert Hoover, 1874-1964; chronology-documents-bibliographical aids”, Oceana Pubns
Immanuel Kant (1993). “Grounding for the Metaphysics of Morals: with On a Supposed Right to Lie because of Philanthropic Concerns”, p.25, Hackett Publishing