Sentence examples for problems were studied from inspiring English sources

Stability problems were studied by many authors (see [31 34]).

Second-order degenerate identification differential problems were studied in [16].

With different supremum operators some similar problems were studied in [12 22].

Other related elasticity problems were studied by Damlamian, Cioranescu and Orlik in [15] and [16].

Some similar problems were studied in [6, 7] and the references therein.

Note that similar optimization problems were studied in [12,20] and [21].

Non-destructive testing problems are studied.

The initial-boundary value problems are studied in [10, 11].

Near-optimality for deterministic control problems was studied in [15 17].

A class of implicit multivalued vector equilibrium problems is studied.

Both initial-Dirichlet and initial-Neumann problems are studied.