Data sources:



A5: BVRcIc photometry by V.P.Goranskij and E.A.Barsukova with the 50-cm Maksutov telescope AZT-5 of the Moscow University Crimean Astronomical Station and CCD Apogee-Alta U8300.
AF,Af: UBVRcIc photometry by V.P.Goranskij with the 60-cm telescope of the Moscow University Crimean Astronomical Station and CCDs FLI PL16803 and PL9142200.
AM: R.Adachi, K.L.Murata, M.Oeda, M.Niwano, K.Shiraishi, K.Iida, F.Ogawa, R.Hosokawa, N.Nakamura, S.Toma, Y.Yatsu, N.Kawai on behalf of the MITSuME collaboration, Astronomer's Telegram #13502, 2020.
As: UBVRcIc photometry by A.V.Zharova with the 60-cm telescope of the Moscow University Crimean Astronomical Station and CCD Apogee Aspen.
AT: D.Denisenko, Astronomer's Telegram #11400, 2018.
C.Litterfield, Astronomer's Telegram #11421, 2018.
P.Gandhi, J.A.Paice, S.P.Littlefair, V.S.Dhillon, P.Chote, T.R.Marsh, Astronomer's Telegram #11437, 2018.
M.Richmond, Astronomer's Telegram #11596, 2018.
M.C.Baglio, D.Russell, T.Al Qaissieh, A.Palado, A.Gabuya, H.Shivkumar, F.Lewis Astronomer's Telegram #12128, #12596, 2018.
J.Ulowetz, G.Myers, J.Patterson, Astronomer's Telegram #12567, 2018.
J.Humbsch, J.Ulowetz, T.Vanmunster, D.Cejudo, J.Patterson, Astronomer's Telegram #12567, 2019.
U.Munari, L.Zampieri, P.Ochner, F.Manzini, Astronomer's Telegram #14492, 2021.
BM: B.Monard, vsnet-alert #23490, 2019.
BR: M.C.Baglio, D.M.Russell, P.Saikia, D.M.Bramich, F.Lewis, Astronomer's Telegram #12608, 2021; M.C.Baglio, J.Homan, D.M.Russell, P.Saikia, D.M.Bramich, F.Lewis, P.Roche, T. Al Qaissieh, A.Gabuya, A.Palado, Astronomer's Telegram #14582, 2021.
HS: Swift Vega magnitude from J. Homan, P.Saikia, M.C.Baglio, D.M.Russell, D.M.Bramich, F.Lewis, P.Roche, D.Altamirano, A.Fabian, J.F.Steiner, K.Gendreau, Astronomer's Telegram #14495, 2021.
MM: V.P.Goranskij with the SAO 1-m Zeiss Telescope and the MMPP photometer polarimeter.
NS: V.P.Goranskij, BV(RU)c photometry with the SAO Zeiss 1-meter reflector and new EEV 42-40 CCD photometer.
SO: UBVRc photometry made by E.A.Barsukova and V.P.Goranskij with CCD EEV 42-40 at 1-m Zeiss telescope of the Special Astrophysical Observatory, Russia.
SV: UBVRcIc photometry made by S.Yu.Shugarov with the 60-cm Zeiss G2 telescope of the Stara Lesna Observatory (Slovakia) and FLI-2 CCD.
VS: J.Hambsch, K.Wenzel, T.Tordai, H.Itoh, L.Cook, G.Stone, Vihorlat Obs. team (P.A.Dubovsky, T.Medulka), P.Nelson, Kyoto U. team, M.Richmond, T.Vanmunster, S.Kiyota, S.Brincat, vsnet-alert #23056; 23081; 23101; 23141; 23159; 23184, 2019.