1. Bostan, I., Popescu, C., Istrate, C., Robu, I., Hurjui, I. (2017). The impact of taxation of the domestic economic transactions on the VAT collection through electronic fiscal devices. Amfiteatru Economic, 19(45), 581–594.
2. Canikalp, E., Unlukaplan, I., Celik, M. (2016). Estimating Value Added Tax Gap in Turkey economic and social development. In Proceedings of the 13th International Scientific Conference on Economic and Social Development. Barcelona, Spain, 437–445.
3. CASE. (2016). Study and Reports on the VAT Gap in the EU-28 Member States: 2016 Final Report [Report FWC No. TAXUD/2015/CC/131.] Available at https://ec.europa.eu/taxation_customs/sites/taxation/files/2016-09_vat-gap-report_final.pdf.
4. CASE. (2018). Study and Reports on the VAT Gap in the EU-28 Member States: 2018 Final Report [Report FWC No. TAXUD/2015/CC/131.] Available at https://ec.europa.eu/taxation_customs/sites/taxation/files/2018_vat_gap_report_en.pdf.
5. Czech Statistical Office. (2018a). Hrubý domácí produkt (HDP) – Metodika (Gross domestic product (GDP) – Methodology). Available at https://europa.eu/youreurope/business/taxation/vat/vat-rules-rates/index_en.htm.