Mathy, A., Ueberhofen, K., Schenk, R., Gregorius, H., Garay, R., Müllen, K., et al. (1996). Third-harmonic-generation spectroscopy of poly(p-phenylenevinylene): A comparison with oligomers and scaling laws for conjugated polymers. Physical Review B, 53(8), 4367-4376. doi:10.1103/PhysRevB.53.4367.