Poisk-1 BIOS source, version '10/07/88'

Copy of http://www.poisk-computer.net.ru/misc/bios_p.7z
Poisk-2 BIOS source, version '06-11-91'

Copy of http://www.poisk-computer.net.ru/misc/bios2poi.7z
EC-1841 BIOS listing, version '12/01/86'

Copied from manufacturer's floppy disks, P/N E11.700.012.D48M and
E11.700.012.D49M.