@inproceedings{ICPR-v2-2004-Ikeda,
	author        = "Osamu Ikeda",
	booktitle     = "{Proceedings of the 17th International Conference on Pattern Recognition, Volume 2}",
	doi           = "10.1109/ICPR.2004.1334100",
	isbn          = "0-7695-2128-2",
	pages         = "220--223",
	publisher     = "{IEEE Computer Society}",
	title         = "{An Accurate Shape Reconstruction from Photometric Stereo Using Four Approximations of Surface Normal}",
	year          = 2004,
}