Some useful/interesting information:

How Kissing Works:

http://people.howstuffworks.com/kissing.htm

The History of the Kiss:

http://people.howstuffworks.com/kissing1.htm

The Anatomy of a Kiss:

http://people.howstuffworks.com/kissing2.htm

Girl’s kiss vs boy’s kiss:

http://www.epjournal.net/filestore/EP05612631.pdf

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