A letter from the pope to the entire Church is called an encyclical.
Eldridge Pope ended in 2003.
Pope Benedict XVI resigned at the end of February 2013; the new pope has yet to be elected.
No, Pope Leo X did not predict the end of the world for 2014. There are no recorded predictions made by Pope Leo X regarding the end of the world.
Your holiness.........
Yes, you can receive a letter (certificate) from the pope. It must be requested well in advance from your pastor or bishop.
In Search of the Pope's Children ended on 2006-11-20.
Pope Paul VI closed Vatican II.
Pope Leo XIII reigned from 20 February 1878 to 20 July 1903.
Lumen Fidei was the first encyclical of Pope Francis.
Encyclical
Brevet