comets which are observed: 29P/S-W1, 64P/SWIFT-GEHRELS, C/2017 K4 (ATLAS). spectroscopic observations of Be-stars: V442 And, QR Vul, 37 Per
comets which are observed: 29P/S-W1, 64P/SWIFT-GEHRELS, C/2017 K4 (ATLAS). spectroscopic observations of Be-stars: V442 And, QR Vul, 37 Per