R.  Bekchiev and Kostova, R., ?The Subfamily Pselaphinae (Coleoptera: Staphylinidae) of South-western Bulgaria: Rila and Pirin Mountains?, Acta Zoologica Bulgarica, vol. 74, pp. 169-174, 2022.

R.  Kostova, Bekchiev, R., and Beshkov, S., ?Coleoptera and Lepidoptera (Insecta) diversity in the central part of Sredna Gora Mountains (Bulgaria)?, Bulletin of the Entomological Society of MaltaBulletin of the Entomological Society of Malta, vol. 10, pp. 75-95, 2019.

M.  Langourov, Simov, N., Bekchiev, R., Chobanov, D., Antonova, V., and Dedov, I., ?Inventory of selected groups of invertebrates in sedge and reedbeds not associated with open waters in Bulgaria?, Acta Zoologica Bulgarica, vol. 70, pp. 487-500, 2018.

R.  Bekchiev and Guéorguiev, B., ?First purposive study of beetles (Coleoptera) from endogean environments in Bulgaria: collection sites and preliminary results?, Biodiversity JournalBiodiversity Journal, vol. 6, pp. 327?340, 2015.

A.  Lapeva-Gjonova, ?Ant-Associated Beetle Fauna in Bulgaria: A Review and New Data?, Psyche, vol. 2013, pp. 1-14, 2013.

B.  Guéorguiev and Ljubomirov, T., ?Coleoptera and Hymenoptera (Insecta) from Bulgarian section of Maleshevska Planina Mountain: study of an until recently unknown biodiversity.?, Acta Zoologica Bulgarica, vol. 61 , pp. 235-276, 2009.

F. J.  Rambousek, ?P?ísp?vek k poznání bulharských Pselaphid? a Scydmaenid??, ?asopis ?eské Spole?nosti Entomologické, vol. 6, pp. 16-24, 1909.

Z.  Karaman, ?Revision der Gattung Trimium Aube (Coll. Pselaph.).?, Acta Musei Macedonici Scientiarum Naturalium - Skopje, vol. 10 , pp. 131-173, 1967.

A.  Lapeva-Gjonova, ?Pselaphinae (Coleoptera: Staphylinidae) from Ant Nests (Hymenoptera: Formicidae) in Southwestern Bulgaria?, Acta Zoologica Bulgarica, vol. 56, pp. 69-73, 2004.

R.  Bekchiev, ?Faunistic review and description of a new species of Pselaphinae (Coleoptera:Staphylinidae) from the Strandzha Mountains (Bulgaria and Turkey)?, Turkish Journal of Zoology, vol. 37, pp. 431-440, 2013.

R.  Bekchiev, ?Description of a new species of Trimium Aubé, 1833 (Staphylinidae: Pselaphinae) from Bulgaria and Greece?, Acta zoologica bulgarica, vol. 65 , p. 289?291, 2013.

R.  Bekchiev and Shishiniova, M., ?A contribution to the Pselaphinae fauna (Coleoptera: Staphylinidae) of the Vitosha Mountain?, Acta Zoologica Bulgarica, vol. 59, pp. 33-39, 2007.

R.  Bekchiev, ?The subfamily Pselaphinae (Coleoptera: Staphylinidae) of southwestern Bulgaria II: Belasitsa Mts.?, Biologia (Bratislava), vol. 66, pp. 506-508, 2011.

R.  Bekchiev, ?The subfamily Pselaphinae (Coleoptera: Staphylinidae) of southwestern Bulgaria. I.?, Historia Naturalis Bulgarica, vol. 19, pp. 51-71, 2008.