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https://www.livescience.com/3328-saliva-secret-ingredient-kisses.html

https://greatergood.berkeley.edu/article/item/subversive_power_of_the_kiss

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5742446/

https://pubmed.ncbi.nlm.nih.gov/14635463/

https://www.ncbi.nlm.nih.gov/pubmed/24114390

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3987372/

https://pubmed.ncbi.nlm.nih.gov/22230150/

https://www.livescience.com/33006-why-do-we-kiss.html

https://link.springer.com/article/10.1007%2Fs10865-015-9695-5