EN
Let X be a Riemann domain over $ℂ^{k} × ℂ^{ℓ}$. If X is a domain of holomorphy with respect to a family ℱ ⊂𝓞(X), then there exists a pluripolar set $P ⊂ ℂ^{k}$ such that every slice $X_{a}$ of X with a∉ P is a region of holomorphy with respect to the family ${f|_{X_{a}}: f ∈ ℱ}$.