A lot of thanks for such a prompt and detailed answer. Frankly speaking, I didn't expect to receive it so soon. God will render you with health and happiness for such a kind and useful doing you perform.
Your letter says that the burial place was quite close, but I didn't find it since it was already about 21:00 when we found the Monument. Museum was closed at that time and it was impossible to get any info. I was travelling with grandgrandson of my grandfather - little Roman who was only 5 months then - that's why we couldn't stay in Finland and visit museum in the morning. However we keep a hope to find my grandfather's grave and will make attempts to go there.
My grandfather, Kuzenko Roman Andreevich, was military veterinarian feldsher. He was called-up in Zhitomir. We don't know his rank. Supposedly he was born in 1913. It's impossible to determine more precisely, since there are no any documents. We have only a marriage certificate, but it's very decrepit and some parts of it are missing. I managed to find out that he was serving in rifle division 122 ÀÏ 44.
His wife and two little sons - born in 1937 and 1939 - stayed in Zhitomir. My father is elder. He told that grandfather was very kind and good person. Since neither grandmother, nor father is alive now it's impossible to get more detailed info.
My father told that granfa's both legs were injured and his friend (unfortunately, we know nothing about him) was carrying him several kilometers to sanitarian car which had to go to hospital. The car was attacked under way and blown up. A few people managed to survive and dived into a forest. My grandfather was among them. He was with some slightly-injured guy. That guy, being scared of all situation, said to grandfa, that it would be hard to save themselves together, but possible for him to do that alone. Then he left my injured grandfather to freeze over and die. That guy really managed to survive. Some time later he told this story to my granny.
In the certificate of grandfather's death a date of January 6, 1940, is indicated. It also says that granfa was killed.
I asked a stuff of "Ukraine Memory Book" to find my grandfather's exact date of birth, however, they had no information. The only thing they said he was "missed on 06.01.1940".