@article{IJPRAI2007,
author = {Zhirong Yang and Zhijian Yuan and Jorma Laaksonen},
journal = {International Journal on Pattern Recognition and Artificial Intelligence},
month = {December},
number = {8},
pages = {1353-1362},
title = {Projective Non-negative Matrix Factorization with Applications to Facial Image Processing},
volume = {21},
year = {2007},
}