Optical variabilities in the Be/X-ray binary system - GRO J2058+42 (CXOU J205847.5+414637) Ü. Kızıloğlu, N. Kızıloğlu, A. Baykal, S. K. Yerli and M. Özbey A&A, 470 3 (2007) 1023-1029 Published online: 30 May 2007 DOI: 10.1051/0004-6361:20077365