@article{Pe�a1999,
	title = {Why do we smile?: On the determinants of the implied volatility function},
	author = {Ignacio Pe{\~n}a and Gonzalo Rubio and Gregorio Serna},
	journal = {Journal of Banking \& Finance},
	month = {Aug},
	number = {8},
	pages = {1151--1179},
	url = {http://www.sciencedirect.com/science/article/B6VCY-3WY41K7-1/1/c1a089f4f5e9535690102c2b58a4adf7},
	volume = {23},
	year = {1999},
	biburl = {http://www.bibsonomy.org/bibtex/29c01763ea214422264a66fdb0a299daa/smicha},
	description = {Journal of Banking & Finance},
	keywords = {Smiles }
}