[en] Incoherent scattering functions S(x,Z) for six rare earth elements Pr, Sm, Gd, Dy, Ho and Yb (59 ≤ Z ≤ 70) were evaluated from the accurately measured whole atom differential incoherent scattering cross sections for 59.54 keV gamma rays at four scattering angles (30 deg, 45 deg, 60 deg and 90 deg). The scattering experiments were conducted in a reflection geometry set up with graded shielding arrangements. A 300 mCi ²⁴¹Am was used as source of 59.54 keV gamma rays. High purity (> 99.99%) thin (μt < 1) elemental foils of the said elements were used as scatterers. A 6 cc LEP-HPGe spectrometer coupled to a PC based 4k MCA was used for recording the scattered gamma ray photons. The measured cross sections and the S(x,Z) values [corresponding to four photon momentum transfer values x = 1.242, 1.84, 2.40 and 3.39A deg^-1 (x = 1/λ sin θ/2)] were compared with the latest experimental values reported in literature and also with the theoretical computations based on Hartree-Fock and Thomas-Fermi model predictions. Possible conclusions are drawn on electron binding and other effects. (author)