Hi, Melody —

These are abbreviations and the sixteen documents of Vatican II.

Here is a reliable source for the documents and their abbreviations:

The 16 Documents of the Second Vatican Council

No.	Abbr.	Latin Title	English Title	Issued
1.	SC	Sacrosanctum concilium	Constitution on the Sacred Liturgy	1963
2.	IM	Inter Mirifica	Decree On the Means of Social Communication	1963
3.	LG	Lumen Gentium	Dogmatic Constitution On the Church	1964
4.	OE	Orientalium Ecclesiarum	Decree On the Catholic Churches of the Eastern Rite	1964
5.	UR	Unitatis Redintegratio	Decree on Ecumenism	1964
6.	CD	Christus Dominus	Decree Concerning the Pastoral Office of Bishops In the Church	1965
7.	PC	Perfectae Caritatis	Decree On Renewal of Religious Life	1965
8.	OT	Optatam Totius	Decree On Priestly Training	1965
9.	GE	Gravissimum Educationis	Declaration On Christian Education	1965
10.	NA	Nostra Aetate	Declaration On the Relation Of the Church to Non-Christian Religions	1965
11.	DV	Dei Verbum	Dogmatic Constitution On Divine Revelation	1965
12.	AA	Apostolicam Actuositatem	Decree On the Apostolate of the Laity	1965
13.	DH	Dignitatis Humanae	Declaration On Religious Freedom	1965
14.	AG	Ad Gentes	Decree On the Mission Activity of the Church	1965
15.	PO	Presbyterorum Ordinis	Decree On the Ministry and Life of Priests	1965
16.	GS	Gaudium et Spes	Pastoral Constitution On the Church In the Modern World	1965

This: 11 §1 Is the Chapter and verse from the document.

• So LG 11§1 is Lumen Gentium, Chapter 11, verse 1
• UR 4§3 is Unitatis Redintegratio, Chapter 4 verse 3

Here is a text version of all the abbreviations that are in the Catechism plus all the books of the Bible correctly spelled out.

Important: Scan through the back of the Catechism. It has some great appendices and glossary stuff.

Hope this helps,

Mike