The directory, known as the Annuario Pontificio, lists the Vatican's official information regarding church leaders and dioceses throughout the world.
Release of the 2013 edition was delayed following Pope Benedict XVI's resignation in Feburary and Francis' election in March.
As is traditional for the reference book, information about Francis, who leads the world's 1.2 billion Catholics, is listed towards the front of the material.
In a departure from previous editions however, the information about the pope is split into two distinct sections, according to Italian media reports, including one at veteran Italian journalist Sandro Magister's site at the Italian newsmagazine l'Espresso.
In the first section, the new pope is described simply as "Francis / Bishop of Rome."
In the 2012 edition, Pope Benedict had also been described that way, but had listed under his title as bishop several other titles normally taken by the pope, including:
“Vicar of Jesus Christ, Successor of the Prince of
the Apostles, Supreme Pontiff of the Universal Church, Primate of
Italy, Archbishop and metropolitan of the Roman province, Sovereign of
Vatican City-State, Servant of the Servants of God.”
While popes have over the centuries developed numerous titles, they also function as a diocesan bishop of Rome, where the apostle Peter is traditionally claimed to be the first bishop of the some 2,000 year old church.
Pope Francis has on several occasions emphasized his role as a bishop, rarely referring to himself as pope or pontiff -- even on the night of his election telling crowds in St. Peter's Square it was "the task of the conclave was to give Rome a bishop."
The 2013 edition of the Annuario Pontificio is also the first since the directory's beginning in the year 1716 to feature a description of a retired pope, Benedict XVI, who is titled as "supreme pontiff emeritus."
In another change from the 2012 copy, the signature under Francis' official portrait is given in Italian and not Latin.
While Benedict previously signed his name in Latin as "Benedictus" (and not the Italian "Benedetto"), Francis has signed his in the Italian "Francesco" (and not the Latin "Franciscus").
Additionally, Benedict's signature appeared with the initials PP following his name, standing for "pope," while Francis' does not.