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		| Paper: | A Spitzer IRS Survey of Wolf-Rayet Stars at 10–20 Microns |  
		| Volume: | 388, Mass Loss from Stars and the Evolution of Stellar Clusters |  
		| Page: | 177 |  
		| Authors: | Ignace, R.; Cassinelli, J.P.; Tracy, G.; Lamers, H.J.G.L.M.; Churchwell, E.B. |  
		| Abstract: | We report on a mid-infrared survey of Wolf-Rayet stars using the Spitzer IRS/SH instrument for types WN4-WN7 and WC4-WC7. Strong emission line spectra are seen, including forbidden emission lines. Surprisingly, the WN stars appear to show broad emission “bumps” that may be consistent with silicate dust grains. |  
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