Letter to the President of the United States of America, His Excellency Franklin Delano Roosevelt on the occasion of the appointment of an Extraordinary Ambassador of the United States of America to the Holy See (January 7, 1940) [Italian] Letter to the President of the United States of America, His Excellency Harry S. Truman (August 26, 1947) [Italian] Letter Quod Sodales, on the occasion of the  International Congress of the Apostleship of Prayer Society (September 19, 1948) [Italian] Letter Acerrimo Moerore, to Hungarian Archbishops and Bishops (January 2, 1949) [Italian] Letter Vix Undecimus to the Religious Fathers of the Society of Jesus (March 12, 1950) [Italian] Letter to H.E. Msgr. José Clemente Maurer, Archbishop of Sucre, on the occasion of the Second National Marian Congress of Bolivia (August 13, 1954) [Spanish]