Raccolta and the Enchiridion of Indulgences

http://www.ebay.com/itm/1952-RACCOLTA-Manual-Indulgences-Prayers-Devotions-/290743018034

Following info is from wikipedia.com The Raccolta is a book, published from 1807 to 1950, that listed Roman Catholic prayers and other acts of piety, such as novenas, for which specific indulgences were granted byPopes. In 1968 it was replaced by the Enchiridion Indulgentiarum,^[1][2] listing fewer specific prayers but including new general grants that apply to a wide range of prayerful actions.

By his bull Indulgentiarum Doctrina of 1 January 1967, Pope Paul VI ordered a revision of the collection of indulgenced prayers and works "with a view to attaching indulgences only to the most important prayers and works of piety, charity and penance".^[8][1] Since then the official collection of the currently indulgenced prayers and good works is called the Enchiridion Indulgentiarum. The first edition appeared in June 1968.^[9] As indicated in an article published on the English edition of L'Osservatore Romano of 12 December 1968, it was only one sixth the size of the last edition of the Raccolta. An English translation on the Internet is provided by Idaho Lay Dominicans. A digested account is given by Catholic Online.

The Enchiridion Indulgentiarum, which is in Latin, differs from the Italian-language Raccolta in listing "only the most important prayers and works of piety, charity and penance". On the other hand, it includes new general grants of partial indulgences that apply to a wide range of prayerful actions, and it indicates that the prayers that it does list as deserving veneration on account of divine inspiration or antiquity or as being in widespread use are only examples^[10] of those to which the first these general grants applies: "Raising the mind to God with humble trust while performing one's duties and bearing life's difficulties, and adding, at least mentally, some pious invocation".^[11] In this way, the Enchiridion Indulgentiarum, in spite of its smaller size, classifies as indulgenced an immensely greater number of prayers than were treated as such in the Raccolta.

The prayers listed in the Raccolta were of Latin Church tradition alone, but the Enchiridion Indulgentiarum includes also prayers from the traditions of the Eastern Catholic Churches, such as the Akathistos,Paraklesis, Evening Prayer, and Prayer for the Faithful Departed (Byzantine), Prayer of Thanksgiving (Armenian), Prayer of the Shrine and the Lakhu Mara (Chaldean), Prayer of Incense and Prayer to Glorify Mary the Mother of God (Coptic), Prayer for the Remission of Sins and Prayer to Follow Christ (Ethiopian), Prayer for the Church, and Prayer of Leave-taking from the Altar (Maronite), and Intercessions for the Faithful Departed (Syrian).

https://www.crossroadsinitiative.com/resource_info/284.htm

This lHandbook of Indulgences is the revised edition of the ENCHIRIDION OF INDULGENCES and the official English translation of the Roman Catholic Church’s book on indulgences.  It includes a list of the works and prayers to which indulgences are attached and therefore serves as an authoritative and very enlightening collection of devotional practices that the pastors of the Catholic Church regard as especially effective at eradicating vice, building virtue, and strengthening the soul in its battle against sin.  Every Catholic should have a copy of this short, understandable, and very practical little book.

The Enchiridion of Indulgences
The formula for obtaining a plenary indulgence are the three constants  plus any one of the variable works  as being worthy of a plenary indulgence.

The three prerequisites (Constants) of a plenary indulgence.

1. Sacramental Confession,
2. Communion, and
3. Prayer for the intention of the Holy Father, all to be performed within days of each other if not at the same time.

 Quotes from 

MISERENTISSIMUS REDEMPTOR

ENCYCLICAL OF POPE PIUS XI ON REPARATION TO THE SACRED HEART :

.. For indeed if any one will lovingly dwell on those things of which we have been speaking, and will have them deeply fixed in his mind, it cannot be but he will shrink with horror from all sin as from the greatest evil, and more than this he will yield himself wholly to the will of God, and will strive to repair the injured honor of the Divine Majesty, as well by constantly praying, as by voluntary mortifications, by patiently bearing the afflictions that befall him, and lastly by spending his whole life in this exercise of expiation.

...making expiation, a duty which is to be fulfilled by fitting exercises of devotion and of the virtues; hence lastly, to omit other things, come the devotions and solemn demonstrations for the purpose of making reparation to the offended Divine honor, which are inaugurated everywhere, not only by pious members of the faithful, but by parishes, dioceses and cities.