A dust component ~2 kpc above the plane in NGC 891 P. Kamphuis, B. W. Holwerda, R. J. Allen, R. F. Peletier and P. C. van der Kruit A&A, 471 1 (2007) L1-L4 Published online: 18 June 2007 DOI: 10.1051/0004-6361:20077951