Brazil's President Dilma Rousseff (L) and Argentina's President Cristina Fernandez de Kirchner attend the final mass of Pope Francis' visit to Brazil, at Copacabana beach in Rio de Janeiro on July 28, 2013. Throngs of pilgrims attending World Youth Day (WYD) spent the night sleeping on the beach before Sunday's final mass, while the city's mayor said he expects up to three million people to pack the beach for the occasion. AFP PHOTO / POOL - LUCA ZENNARO