An Investigation of Be/X-ray Pulsars with OGLE-III Data
  We have studied five seasons of OGLE-III data for eight SMC Be/X-ray pulsars for which no other survey data were available. We have determined orbital periods for four of these binary systems, one of which also shows nonradial pulsations. Optical identification of SMC X-2 is reconsidered, but no periods were found for either of the two possible candidates. 
P. C. Schmidtke, A. P. Cowley, A. Udalski