Contents

Astronomy Letters

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Vol. 47, No. 8, 2021

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The Growth Rate of Supermassive Black Holes and Its Dependence on the Stellar Mass of Galaxies at the Present Epoch

S. A. Prokhorenko and S. Yu. Sazonov p. 515  abstract

Estimation of the Radial Scale Length and Vertical Scale Height of the Galactic Thin Disk from Cepheids

V. V. Bobylev and A. T. Bajkova p. 534  abstract

Search for Evolutionary Changes in the Periods of the Double-Mode Cepheid TU Cas

L. N. Berdnikov and E. N. Pastukhova p. 544  abstract

Spectroscopic Variability of the Compact Planetary Nebula Hb 12

N. P. Ikonnikova, I. A. Shaposhnikov, V. F. Esipov, M. A. Burlak, V. P. Arkhipova, A. V. Dodin, S. A. Potanin, and N. I. Shatsky p. 560  abstract

On the Hall Instability in Protostellar Disks

V. Yu. Zakharov and T. G. Chernova p. 581  abstract

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