anharmonique
1979 / Large amplitude simple pendulum: A Fourier analysis / R. Simon ; R. P. Riesz / American Journal of Physics 47 (1979) p. 890 [doi]
1981 / Comments on Fourier analysis of the simple pendulum / Donald E. Hall / American Journal of Physics 49 (1981) p. 792 [doi]
1984 / Small oscillations which are not harmonic / A. Ronveaux / American Journal of Physics 52 (1984) p. 618 [doi]
2008 / Inharmonicité des modes d'oscillation des cordes vibrantes / Christophe Hernandez ; Claude Le Breton / Bulletin de l'Union des Physiciens 904 (2008) p. 667 [lien]