The effect of deformation-dependent mass term on the Bohr model in the presence of rigidity parameter for Kratzer potentialNahid Soheibi, Mahdi Eshghi and Mohsen BigdeliEur. Phys. J. Plus, 134 5 (2019) 208DOI: https://doi.org/10.1140/epjp/i2019-12574-5