Nebosis, R. S., Heusinger, M. A., Semenov, A. D., Lang, P. T., Schatz, W., Steinke, R., et al. (1993). Ultrafast photoresponse of an YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7-δ</sub> film to far-infrared radiation pulses. _Opt. Lett._, _18_(2), 96&ndash;97.