@article {annals2004,
	title = {On the forward and backward algorithms of projection pursuit},
	journal = {Annals of Statistics},
	volume = {32},
	number = {1},
	year = {2004},
	pages = {233{\textendash}244},
	doi = {10.1214/aos/1079120135},
	url = {http://doi.org/10.1214/aos/1079120135},
	author = {Zhu, Mu}
}
