Tham khảo DAR_1

  1. ↑ Balkan Birds: Thirty Five Years of Bulgarian Aircraft Production

Tài liệu

  • Air Enthusiast No.94 July/August 2001 pp18–30
  • Insignia Issue 8 March/April 1998 pp132–135
  • Air Power of the Kingdom of Bulgaria Part III
  • Bernád, Dénes. “Balkan Birds: Thirty Five Years of Bulgarian Aircraft Production”. Air Enthusiast. Stamford, Lincs, UK: Key Publishing (94, July/August 2001): 18–30. ISSN 0143-5450. Chú thích có tham số trống không rõ: |month= (trợ giúp)
  • The Illustrated Encyclopedia of Aircraft (Part Work 1982-1985). Orbis Publishing.