## On some properties of a set of boundary value problems.(Russian)Zbl 0533.35015

The minimal and the maximal operators $$L_ 0$$ and $$\hat L$$ for the linear differential operator $${\mathcal L}$$ in a domain $$\omega \subset R^ n$$, are conidered. A closed operator L is called a boundary value problem, if $$L_ 0\subset L\subset \hat L$$. If we know a correct problem, then we can find the set of all correct boundary value problems. Some examples are given.