Isolation and Characterization of Two Pigment-dispersing Hormones from the Whiteleg Shrimp, Litopenaeus vannamei Ohira, Tsuyoshi and Tsutsui, Naoaki and Kawazoe, Ichiro and Wilder, Marcy N., Zoological Science, 23, 601-606 (2006), DOI:http://dx.doi.org/10.2108/zsj.23.601