It's in "The First Christian Theologians" by G.R. Evans.
"In AD 535 the voyager Cosmas Indicopleustes reports having encountered Christian coreligionists 20 years earlier in ports along the South China costs and in southern India, Sri Lanka, Bangladesh and Thailand."
I am not sure about in southern Sri Lanka, in southern Bangladesh and in southern Thailand as well or "in southern" is related to India only?
And if it would be about southern parts of all these countries, how one should write: "in southern India, in southern Sri Lanka, in southern Bangladesh and in southern Thailand"?
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