Adam of Bremen, Gesta Hammaburgensis ecclesiae pontificium, from1076
„Praeterea unam adhuc insulam recitavit a multis in eo repertam occeano, quae dicitur Winland, eo quod ibi vites sponte nascantur, vinum optimum ferentes. Nam et fruges ibi non seminatas habundare, non fabulosa opinione, sed certa comperimus relatione Danorum. „
Eiríks saga rauða is from 1264 and the Grænlendinga saga is from the Flateyarbok from the 14th century, but it is possible that the origins go back to the twelfth century. so we have no eyewithnesses.