Thank you for the hint, Smarty. It worked!
However, I was hoping for scans of the original magazine, not transcribed articles.
Actually, I was looking for any information and, particularly, photos of Bulgarian military aircraft. I found only on article of interest to me, titled: Солунското споразумение и въздушната отбрана на България

I already posted my request for help with photos on another thread of this forum.
If anyone can assist me with photos/scans of Bulgarian fighter aircraft (1919-1947) that I can publish, I would very much appreciate it. Of course, the name of the contributor will be mentioned, as requested.

Thank you,

Denes