Top: part of the Fourier spectrum where the period-spacing pattern was found, with the pulsation periods of the pattern marked by dashed lines. Middle: detected period-spacing pattern. Bottom: two model period-spacing patterns, for M = 1.6 M_⊙, solar metallicity, α_MLT = 1.8, f_ov = 0.015 H_p, and X_c = 0.36. The models have a constant extra diffusive mixing D_mix in the radiative region of 0 cm² s^-1 (full black) and 1 cm² s^-1 (dashed grey), respectively.