Forensic expert Francisco Etxeberria (R) and archaeologist Almudena Garcia Rubio hold pictures showing the remains of niches, one of them appeared with the letters M.C. on it, found in the crypt of Trinitarian convent as they pose outside the convent in Madrid, January 26, 2015. Researchers are undergoing the second phase of a project to find the remains of Spanish novelist Miguel de Cervantes, the creator of "Don Quixote", who requested to be buried in the convent as the Trinitarian religious order had helped to pay a ransom to release him from slavery after he was captured by Moorish pirates. [Photo/Agencies]

The remains of a coffin with the letters M.C. on it is displayed on a table inside the crypt of Madrid's Trinitarian convent in this handout picture released by Madrid's City Hall, January 26, 2015. [Photo/Agencies]

Specialists use ground-penetrating radar to peer into the sub-soil beneath Trinitarian convent in a quest to find the remains of Spanish novelist Miguel de Cervantes, in central Madrid, April 28, 2014. [Photo/Agencies]