Question: In 1455, Donatello released what famous work of art?
About the article "Donatello", section "Main works".

Candidate passages:
Representation in art and literature.
Famous sculptures of David include (in chronological order) those by:  Donatello (c. 1430 – 1440), "David" (Donatello)  Andrea del Verrocchio (1476), "David" (Verrocchio)  Michelangelo (1504), "David" (Michelangelo)  Gian Lorenzo Bernini (1624), "David" (Bernini)  Antonin Mercié (1873)  
The Penitent Magdalene is a wooden sculpture of Mary Magdalene by the Italian Renaissance sculptor Donatello, created around 1453-1455.
The sculpture was likely commissioned for the Baptistery of Florence.
The piece was received with astonishment for its unprecedented realism.
It is currently housed in the Museo dell'Opera del Duomo in Florence.
The wood used by Donatello is that of White poplar. 
Donatello returned to Florence in 1453.
The Judith and Holofernes, begun for the Duomo di Siena date from 1455 to 1460 but were later acquired by the Medici.
Until 1461, Donatello remained in Siena, where he created a "St. John the Baptist", also for the Duomo, and models for its gates, now lost.
For his last commission in Florence, Donatello produced reliefs for the bronze pulpits in the church of San Lorenzo, with help from students Bartolomeo Bellano and Bertoldo di Giovanni.
Donatello provided the general design and personally executed the "Martyrdom of St. Lawrence" and the "Deposition from the Cross"; he worked on the reliefs of "Christ before Pilate" and "Christ before Caiphus", with Bellano.
This work is characterized by an intense, free, indeed sketchy and suggestively unfinished — in Italian a "non-finito" — technique that heightens the dramatic effect of the scenes and emphasizes their spiritual intensity.
Donatello died in Florence in 1466 and was buried in the Basilica of San Lorenzo, next to Cosimo de' Medici the Elder. 
Documentation about the work is scarce.
The Renaissance art historian Giorgio Vasari mentions it as work with no flaws and a perfect anatomy.
Executed by Donatello when he was more than sixty years old, after he had spent a decade in Padua.
The dating has been established indirectly, basing on that of a copy from Neri di Bicci's workshop (now in the Museum of the Collegiate of Empoli), known to be from 1455.
In 1500 it was in the city's baptistery.
According to an Italian historian, it was seen by Charles VIII of France in the 1480s, when he was camped with his army near Florence.
The work was damaged by the 1966 flood of the Arno River.
A program of restoration was finished in 1972.
At the time that restoration was begun, the work was painted dull brown.
A restorer, beginning the restoration, while washing the feet of the Maddalena, discovered a tiny golden patch.
The restoration work thus included removal of all the darkness which had been applied at some negative time in history. 
The tomb monument was the first collaboration between Donatello and Michelozzo, who went on to collaborate on the tomb of Cardinal Rainaldo Brancacci in the Church of Sant'Angelo a Nilo in Naples, the tomb of Papal Secretary Bartolomeo Aragazzi in what is now the Duomo of Montepulciano, and the external pulpit of the Duomo of Prato.
At the time of their partnership, Donatello was already well known for his statues of prophets and saints for the Duomo and Orsanmichele, while Michelozzo was more obscure.
Both had worked for a time for Ghiberti, whose workshop then led Florentine sculpture.
Nearly every element of the tomb monument has been attributed to both Donatello and Michelozzo by different art historians.
These characterizations are mostly of historiographical interest: attribution to Donatello is more of an indication of what is valued by each commentator than any objective criteria; often, aspects are attributed to Michelozzo explicitly because they are "less well executed".
Descriptions from 1475 to 1568 attribute all of the tomb except for the figure of Faith to Donatello.
Some modern sources reverse this dichotomy, attributing all of the tomb to Michelozzo with the exception of the gilded bronze effigy.
Some sources credit Donatello only with the bronze effigy.
According to Janson, of the marble work, only the "putti" can be attributed to "Donatello’s own hand".
Donatello’s alleged deficiencies in casting or in architecture have been proposed as the reason for his partnership with Michelozzo, in addition to his busy schedule.