In the fifth century Estonians built the first fortress at Tarbatu — from which both
the modern Estonian name of Tartu and the Germanic name of Dorpat derive: Batten, Alan Henry (1988). Resolute and Undertaking Characters. Springer. ISBN978-90-277-2652-0.
In the fifth century Estonians built the first fortress at Tarbatu — from which both the modern Estonian name of Tartu and the Germanic name of Dorpat derive: Batten, Alan Henry.Resolute and Undertaking Characters : []. — Springer, 1988. — ISBN 978-90-277-2652-0.
