@conference {cCasas94b,
	title = {Morphological filter for lossless image subsampling},
	booktitle = {IEEE International Conference on Image Processing{\textquoteright}94},
	year = {1994},
	pages = {903{\textendash}907},
	isbn = {0-8186-6950-0},
	author = {Casas, J. and Torres, L.}
}
