Gulbene

РГВА. Ф. 37977. Оп. 1. Д. 681. Л. 88–89.
Agreement protocol of representatives of the Red and Latvia Armies on the establishment of Soviet military bases on the territory of Latvia
17 June 1940
Russian State Military Archive
Coll. 37977, ser. 1, fold. 681, ff. 88–89.

Certified copy