Wang, G., Harpole, C. E., Paulose, J., & Cassone, V. M. (2014). The role of the pineal gland in the photoperiodic control of bird song frequency and repertoire in the house sparrow, Passer domesticus. Hormones And Behavior, 65(4), 372-9. https://doi.org/10.1016/j.yhbeh.2014.02.008