Historical Grammar of Old Prussian

The research of Old Prussian faces more problems than the research of cognate Lithuanian and Latvian languages because Old Prussian (= Prussian) has been poorly presented in written documents. Historical Grammar of Old Prussian (= HGOP) deals with many debatable problems when synchronical and diachronical aspects of Prussian phonetics (as well as spelling), derivation and especially inflexion are touched upon. This is done basing on 4 volumes of former Etymological Dictionary of Old Prussian and on works, referred to in this Dictionary. I do not discuss problems of Prussian syntax which is enough Germanized in attested documents.