Hello,
Those loudspeakers are one of most popular speakers made in Poland i 70's/80/s. Those were first polish speakers made in "hi-fi".
You can find a lot of information using polish name - Unitra ZG40c ("ZG" means "Zestaw Głośnikowy" which means "Loudspeakers set" ) 40 Watts, version "c") - typing in google polish name of them, you will find A LOT of informations.
Woofer is GDN25/40/x (GDN - Głośnik Dynamiczny Niskotonowy = Dynamic Woofer Loudspeaker, 25 cm diameter, 40 W, x Ohm)
mid - GD12/15/x (Głośnik Dynamiczny = Dynamic Loudspeaker, 12 cm diameter, 15 W/x Ohm)
twitter - GDWK9/40/x (Głośnik Dynamiczny Wysokotonowy Kopułkowy = Dynamic Loudspeaker Twitter Dome 9 cm diameter, 40 W, x Ohm)
GDN25/40 firsty were on Pioneer license, then it was Unitra TONSIL.
Good polish loudspeakers from 70's/80's.
