Bivalvia

Protobranchia Pelseneer, 1889

Selection of related publications
Isakar, M. 1991. Harjuan (Late Ordovician) new Bivalves and a new Gastropod from North Estonia. Acta et Comentationes Universitatis Tartuensis 934, 12, 43-60. Töid geoloogia alalt, XII. Eesti Ordoviitsiumi paleontoloogia ja stratigraafia, pp. 43-60.
Isakar, M. & Sinitsyna, I. 1985. Redescription of E. Eichwald's Ordovician bivalve species. Proceedings of the Academy of Sciences of the Estonian SSR. Geology 34, 2, 46-54.
Bekker, H. 1921. The Kuckers Stage of the Ordovician Rocks in NE Estonia. Acta Univ. Tartu A II, 1, 1-90.