Bechev, D. & Pavlova, A., 2016. Fungus gnats (Diptera: Bolitophilidae, Diadocidiidae,  Ditomyiidae, Keroplatidae and Mycetophilidae) of  Vrachanska Planina Mountains. ZooNotes Supplement, 3, pp.169-179. Available at: http://web.uni-plovdiv.bg/bechev/Bechev_pdfs/Mycettopohiloidea%20Vrachanski%20Balkan.pdf.