Differ. Uravn., 1975 Volume 11, Number 9,Page 1713(Mi de2561)
Letters to the Editor
Letter to the editors: "The solvability of the Dirichlet problem for an elliptic equation of order $2l$ in the class $W_2^{(2l)}$" (Differencial'nye Uravnenija 9 (1973), 2048–2051)