Witam After this morning's seminar, here seem to be a few articles on grey extinction and the \ddot{a}/a > 0 interpretation of the SNe Ia experiments: http://arxiv.org/abs/0909.0231 Grey Milky Way Extinction from SDSS Stellar Photometry Authors: Evgeny Gorbikov, Noah Brosch http://arxiv.org/abs/astro-ph/0701259 Redshift-distance relations from type Ia supernova observations. New constraints on grey dust models Authors: A.R. Robaina, J. Cepa http://arxiv.org/abs/astro-ph/0603833 The Impact of Cosmic Dust on Supernova Cosmology Authors: Pier Stefano Corasaniti http://arxiv.org/abs/astro-ph/0505446 No evidence of "gray" dust from composite quasar spectra Authors: Chris J. Willott http://arxiv.org/abs/astro-ph/0410501 Limiting the dimming of distant type Ia supernovae Authors: Linda Ostman, Edvard Mortsell http://arxiv.org/abs/astro-ph/0306459 Extinction by grey dust in the intergalactic medium Authors: Ernst Fischer pozdr boud