SIGMA observation of the sky region containing the COS‐B source 2CG135+01

The region of the sky containing the high energy gamma‐ray source 2CG 135+01 was observed by SIGMA on 1990, July 28–30th. The images obtained were searched for positive emission from the known candidate counterparts. No significant excess was detected. Upper limits in the hard X‐ray range are presented and discussed in the light of the present observational status.