Arellano Ferro, A; Rosenzweig, P; Luna, A; Deras, D; Muneer, S; Giridhar, S; Michel, R
(WILEY-VCH Verlag GmbH & Co., 2018-02)
Based on photometric data obtained between 1935 and 2017, O −C diagrams were built for 22 RR Lyrae stars in the globular cluster NGC 6171, leading to the discovery of secular period changes in four variables for which we ...