Supported by the National Natural Science Foundation of China (Grant No. 10673005);Foundation of the Chinese Academy of Sciences (Grant No. KJCX2-YW-T13)
Revised Hipparcos data were released by van Leeuwen in 2007.In this article revised Hipparcos trigo-nometrical parallaxes are used to derive a period-luminosity zero-point in the optical V band.Adopting a fixed slope ...