Humane Vitae (Of Human Life) - Pope Paul VI, 1968
http://www.vatican.va/holy_father/paul_vi/encyclicals/documents/hf_p-vi_enc_25071968_humanae-vitae_en.html
Familiaris Consortio - On the Role of the Christian Family in the Modern World - Pope John Paul II, 1981
http://www.vatican.va/holy_father/john_paul_ii/apost_exhortations/documents/hf_jp-ii_exh_19811122_familiaris-consortio_en.html
Evangelium Vitae (The Gospel of Life) - Pope John Paul II, 1995
http://www.vatican.va/holy_father/john_paul_ii/encyclicals/documents/hf_jp-ii_enc_25031995_evangelium-vitae_en.html
Donum Vitae (The Gift of Life) - Instruction on Respect for Human Life in its Origin and on the Dignity of Procreation: Replies to Certain Questions of the Day - Sacred Congregation for the Doctrine of the Faith, 1987
http://www.vatican.va/roman_curia/congregations/cfaith/documents/rc_con_cfaith_doc_19870222_respect-for-human-life_en.html
Preparation for the Sacrament of Marriage - Pontifical Council for the Family, 1996
http://www.vatican.va/roman_curia/pontifical_councils/family/documents/rc_pc_family_doc_13051996_preparation-for-marriage_en.html