Please show where devotion to Mary was practiced by the Ante-Nicene church fathers. Thanks
Buy the book.
Why?
Ah! You've located one of my areas of ignorance: I know little about the Ante-Nicene Fathers. If I were researching this question, though, I'll tell you one of the first places I'd look: Mary Through the Centuries: Her Place in the History of Culture, by Jaroslav Peliken.
That, and studies of the earliest liturgical hymns; and books on the catacombs, which are full of devotional clues of various kinds. I do know there are inscriptions like "Beata Maria semper virgine, ora pro nobis."
I know some of the Greek Marian hymns are very ancient. Kolokotronis, can you help us out?