Hardman, S. I., Zollinger, S. A., Koselj, K., Leitner, S., Marshall, R. C., & Brumm, H. (2017). Lombard effect onset times reveal the speed of vocal plasticity in a songbird. The Journal of Experimental Biology, 220(6), 1065-1071. doi:10.1242/jeb.148734.