Diagonals of separately continuous multi-valued mappings (in Ukrainian)

We solve the problem on a construction of a separately continuous mapping with the given diagonal, which is the pointwise limit of a sequence of continuous mappings with values in an equiconnected space. We construct an example of a closed-valued separately continuous mapping $fcolon [0,1]^2multimap mathbb R$ with an everywhere discontinuous diagonal. The example shows that the results on points of joint continuity for compact-valued separately continuous mappings can not be generalized to the case of closed-valued mappings.