2775 20160701171710.0 10.1017/S1743921312012197 DOI ASTROimport-932 Van de Steene, G. C. 2012 A Herschel study of Planetary Nebulae We present Herschel PACS and SPIRE images of the dust shells around the planetary nebulae NGC 650, NGC 6853, and NGC 6720, as well as images showing the dust temperature in their shells. The latter show a rich structure, which indicates that internal extinction in the UV is important despite the highly evolved status of the nebulae. Exter, K. M. van Hoof, P. A. M. Lim, T. L. Barlow, M. J. Matsuura, M. Ueta, T. IAU Symposium 283 2012 514-515 http://esoads.eso.org/abs/2012IAUS..283..514V published in NONREF