Given the following context:

At this stage of its development, Sicilian Baroque still lacked the freedom of style that it was later to acquire. Giovanni Battista Vaccarini was the leading Sicilian architect during this period. He arrived on the island in 1730 bringing with him a fusion of the concepts of Bernini and Borromini, and introduced to the island's architecture a unified movement and a play of curves, which would have been unacceptable in Rome itself. However, his works are considered of lesser quality than that which was to come. Notable works which date from this period are the 18th century wings of the Palazzo Biscari at Catania; and Vaccarini's church of Santa Agata, also in Catania. On this building Vaccarini quite clearly copied the capitals from Guarino Guarini's Architettura Civile. It is this frequent copying of established designs that causes the architecture from this period, while opulent, also to be disciplined and almost reined in. Vaccarini's style was to dominate Catania for the next decades.
A second hindrance to Sicilian architects' fully achieving their potential earlier was that frequently they were only rebuilding a damaged structure, and as a consequence having to match their designs to what had been before, or remained. The Cathedral of San Giorgio at Modica (Illustration 10) is an example. It was badly damaged in the earthquake of 1613, rebuilt in 1643 in a Baroque style while keeping the medieval layout, then damaged again in 1693. Rebuilding again began in 1702, by an unknown architect. Finally, Rosario Gagliardi oversaw the façade's completion in 1760, but the compromises he had to make in deference to the existing structure are obvious. While Gagliardi used the same formulae he used so successfully at the church of San Giorgio in Ragusa, here in Modica the building is heavier, and lacks his usual lightness of touch and freedom of design.

answer the following question:

What is the full name of the Sicilian architect that worked on the Cathedral of San Giorio? 

Rosario Gagliardi