@incollection{,
address  = {},
author = {Birkmann, Thomas},
booktitle = {The Nordic Languages},
keywords = {Birkmann, Thomas (1955-)},
pages = {691-697},
title={From Ancient Nordic to Old Nordic: Definition and delimitation of the period},
uniqueid = {2438281},
url = {http://opac.regesta-imperii.de/id/2438281},
year = {2002}
}