I have contributed material to this month’s Heinrich Köhler auction in Wiesbaden, 19 - 24 April 2021.
There are single items and Yellow Pages larger lots from Imperial and Soviet Russia and, notably, for Armenia where a large part of my remaining stock appears at Lots 10272 and 10276. A nice Zemstvo album page - the stamps are ex Fabergé - is buried at Lot 10203 and a very rare Soviet bisect appears at Lot 1760 with a give-away Start price of 150€ ….
You can search at heinrich-koehler.de by number but I find the listing at philasearch.com easier to use for country listings. Both sites show extensive and often complete scans of each auction lot.