The asaphid trilobite fauna : its rise and fall in balticaPärnaste, Helje; Bergström, JanPalaeogeography, Palaeoclimatology, Palaeoecology2013 / p. 64 - 77 https://doi.org/10.1016/j.palaeo.2013.06.007 Journal metrics at Scopus Article at Scopus Journal metrics at WOS Article at WOS

High-resolution trilobite stratigraphy of the Lower–Middle Ordovician Öland Series of BaltoscandiaPärnaste, Helje; Bergström, Jan; Zhiyi, ZhouGeological magazine2013 / p. 509-518 : ill https://pubs.geoscienceworld.org/geolmag/article-abstract/150/3/509/299539/High-resolution-trilobite-stratigraphy-of-the https://doi.org/10.1017/S0016756812000908 Journal metrics at Scopus Article at Scopus Journal metrics at WOS Article at WOS

Lower to middle Ordovician trilobite faunas along the Ural border of BalticaPärnaste, Helje; Bergström, JanBulletin of Geosciences2014 / p. 431 - 450 https://doi.org/10.3140/bull.geosci.1448 Journal metrics at Scopus Article at Scopus Journal metrics at WOS Article at WOS

Trilobites and biofacies in the Early-Middle Ordovician of Baltica and a brief comparison with the Yangtze PlateBergström, Jan; Pärnaste, Helje; Zhiyi, ZhouEstonian journal of earth sciences2013 / p. 205-230 : ill https://artiklid.elnet.ee/record=b2651566*est https://doi.org/10.3176/earth.2013.16 Journal metrics at Scopus Article at Scopus Journal metrics at WOS Article at WOS