I never really questioned it since i grew up watching these soviet cartoons, but the work of David Cherkasky is very….recognizable.
Very little shows up when i googled him, i don’t even know whether he’s still alive or not. But he had a very unique style of meshing cutout animation with hand drawn sequences, and an unconventional character art style.
All of his most known works he directed were produced under Kyivnaukfilm during USSR including Doctor Aibolit (literal translation “doctor ouch it hurts”) linked above,
Adventures of Captain Wrongel, and my personal favourite is his adaptation of Treasure Island. I watched it nonstop on VCR every time i was back in russia. I really like some of the moving perspective animation. it is very clear the man loved ships and pirates
This is the only photo i could find of him in my first search, pictured far right, along with Yuri Norstein(center), and Eduard Vasilevich(left) the original designer of russian winnie the pooh.