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Published online by Cambridge University Press: 14 August 2015
From an analysis of the IRAS data of Roberts 22,Ml-92,M2-9,OH 231.8+4.2,M1-91,MWC 922,Hen 401,Mz-3,OH 19.2-1.0 and OH 26.5+0.6 it is found that the characteristics of the dust shells or disks around these objects are similar to that observed in planetary nebulae. These ten objects may be described as transition objects evolving from the tip of AGB towards left in the HR diagram. The bipolar and disk geometry of the dust envelopes around these objects may be the result of large angular momentum of the progenitor star or the central objects may be evolved binary systems embedded in thick disks formed from severe mass loss.