Human tears contain a chemosignal.
Gelstein S, Yeshurun Y, Rozenkrantz L, Shushan S, Frumin I, Roth Y, Sobel N.
Gelstein S, et al. Among authors: sobel n.
Science. 2011 Jan 14;331(6014):226-30. doi: 10.1126/science.1198331. Epub 2011 Jan 6.
Science. 2011.
PMID: 21212322