1. A clarification from the Sofia Muslim EducationalCultural [Cooperative] Organisation "Istikbal"/Future. (1938, March 16). Central state archive (f. 1k, op. 4, a.e. 531, l. 5.). Bulgarian State Archive, Sofia.
2. A letter from the Pleven Regional Directorate, Pleven, to the Ministry of Internal Affairs and National Health, Sofia. (1938, September 27). Central state archive (f.264k, op. 2, a.e. 5204, l. 21.). Bulgarian State Archive, Sofia.
3. A letter from the Sliven Economic Association to the Minister of Internal Affairs and National Health. (1941, September 10). Central state archive (f. 190k, op. 3, a.e. 114, l. 2–2back.). Bulgarian State Archive, Sofia.
4. A request letter from the neighborhood CulturalCharitable Association “Ivan Krastitel”, Sofia, to the head of 10th police station]. (1938, March 30). Central state archive (f. 1k, op. 4, a.e. 531, l. 1–1back.). Bulgarian State Archive, Sofia.
5. Application from the managing body of the Branch Tinsmith Craftsmanship Association “Balkan,” town V. Tarnovo. (1938, June 6). Central state archive (f. 264k, op. 2, a.e. 5204, l. 5–10.). Bulgarian State Archive, Sofia.