SIMBAD references

S5 0716+714 and 3C 273 are frequently studied blazars, which show obvious optical variabilities with different timescales. Using the 1.0 m telescope at the Yunnan Observatory, we monitored the two sources. For S5 0716+714, we report 990 observations during the monitoring duration from JD 2458536 to JD 2458540. For 3C 273, there are 884 observations during the monitoring duration from JD 2458539 to JD 2458542. Based on those observations, we obtain the following results. (1) For S5 0716+714, there lie intraday optical variabilities (IDVs), with timescales from 0.31 hours to 2.64 hours. For 3C 273, it is possible that there lie IDVs, with timescales from 0.36 hours to 0.49 hours. (2) The time delay of S5 0716+714 is τ_RI_ = 3.46 min between R and I bands, and the time delay of 3C273 is τ_IV_ = 6.42 min between I and V bands. (3) We find that, for S5 0716+714, there lies a suspected intra-day period, P ≃ 185.78 min; for 3C 273, there lie intra-day periods, which are about ∼ 60 min and ∼ 80 min.