Isabelle Bloch Lars Aurdal Domenico Bijno Jens Müller 0003 Estimation of class membership functions for grey-level based image fusion. 268-271 1997 ICIP (3) http://computer.org/proceedings/icip/8183/volume3/81830268abs.htm db/conf/icip/icip1997-3.html#BlochABM97