original description
(of Tracheoniscus difficilis Radu, 1950) Radu, V. G. (1950). Isopode terestre recoltate în regiunea Poiana – Rusca, Hunedoara. <em>Lucrările Sesiunii Generale Ştiinţifice din 2-12 Iunie 1950.</em> Pp. 1-33. Bucureşti: Academia Republicii Populare Româîne. [details] Available for editors 
basis of record
Schotte, M., B.F. Kensley & S. Shilling. (1995 onwards). World list of Marine, Freshwater and Terrestrial Crustacea Isopoda. National Museum of Natural History Smithsonian Institution: Washington D.C., USA - no longer online. [website archived on 2018-01-25]. [details]
additional source
Schmalfuss, H. (2003). World catalog of terrestrial isopods (Isopoda: Oniscidea). <em>Stuttgarter Beiträge zur Naturkunde Serie A (Biologie).</em> 654: 1-341., available online at https://www.biodiversitylibrary.org/page/60882444 [details] Available for editors 
From editor or global species database
type locality Romania [details]