SIMBAD references

We present the results of UBrH_αz monitoring of a sample of T Tauri stars. The method of differential CCD photometry was applied. The observations span a range of ten days and show that eleven out of twelve sources varied during this time interval. These variations are correlated in all bands. Periods were detected (confidence level 99.99%) for eight out of eleven variable stars; one additional period was found at the 99.9% confidence level. Of those, one (BP Tau) agrees with previously published periods; two, GM Aur and IQ Tau, do not; six are new detections of periodicities. The sample is drawn from the Taurus-Auriga and Cepheus IV star-forming regions.