Serotonin signaling is a very early step in patterning of the left-right axis in chick and frog embryos
Current Biology (2005) - Comments
pubmed: 15886096  doi: 10.1016/j.cub.2005.03.044  issn: 0960-9822 

Takahiro Fukumoto, Ido P. Kema, Michael Levin