What the heck is this you may well ask?
" PG contains more than 160 volumes of Greek material (with Latin translations) relevant to the study of the history of the Christian Church from its beginnings through the Council of Florence in 1439.
J.-P. Migne, a priest from 1824-1833, moved to Paris and began the work of assembling an enormous body of early texts from 1833 till his death in 1873.
PG is a collection of the writings of the church leaders who wrote in Greek, including both the Eastern "Fathers" and those Western Christians who wrote before the Latin takeover of the West in the third century.
PG's coverage extends to 1439, the date of the Council of Florence."