Pandey, J. C; Singh, K. P; Sagar, R; Drake, S. A
(Indian Academy of Sciences, 2002-03)
We present photometric observations of four stars that are optical counterparts of soft X-ray/EUV sources, namely 1ES 0829+15.9, 1ES0920-13.6, 2RE J110159+223509 and 1ES 1737+61.2. We have discovered periodic variability ...