Danilin, A. R. Asymptotic behaviour of bounded controls for a singular elliptic problem in a domain with a small cavity. (English. Russian original) Zbl 0934.49017 Sb. Math. 189, No. 11, 1611—1642 (1998); translation from Mat. Sb. 189, No. 11, 27-60 (1998). Reviewer: U.Raitums (Riga) MSC: 49K20 35C20 35B37