Here is a rare sheet of 42 airmail labels from Mountainous Karabagh.
Nagorno-Karabakh or Mountainous Karabagh is a landlocked region in the South Caucasus, lying between Lower Karabakh and Zangezur and covering the southeastern range of the Lesser Caucasus mountains. (wikipedia)
Year: ?, Gummed. Günter Mair's catalogue no: - not listed, imperforated, dark violet-blue/white, sheets