The standard reference for Catholic dogmatic theology. Reveals the historical development of Church doctrine through chronological arrangement of key passages from principal magisterial source documents. Image links to free 1954 edition, which employs the pre -1963 marginal numbering system. ISBN recommendation: 0898707463
Papal letters to the Universal Church or, in many cases, especially before Vatican II, to the Bishops in communion with the Holy See. Worthy of special attention besides Rerum Novarum (see previous post) are Quadragesimo Anno, Mater et Magistra, Pacem in Terris, Populorum Progressio, Laborum Exercens, Sollicitudo Rei Socialis, Centesimus Annus, Caritas in Veritate, Fides et Ratio, and Spe Salvi. As of this post, the Vatican has online the encyclicals of Leo XIII, Pius X, Benedict XV, Pius XI, Pius XII, John XXIII, Paul VI, John Paul II, Benedict XVI, and Francis. ISBN recommendation: 0-87650-259-1
Statement on the origin of life and evolution. Image links to EWTN translation. See also Appendix I, Joseph Cardinal Ratzinger: In the Beginning…, for a contemporary meditation on the Genesis creation accounts.
A joint Catholic-Orthodox declaration, proclaimed 7 December 1965, committing the excommunications, related to Papal embassy to Constantinople in 1054, to oblivion. Image links to Vatican translation.