## Abstract We describe the essential spectrum of a hypoelliptic pseudoβdifferential operator which is the sum of a constantcoefficients operator and an operator with coefficients vanishing at infinity. (Β© 2007 WILEYβVCH Verlag GmbH & Co. KGaA, Weinheim)
A proof of the hypoellipticity of formally hypoelliptic differential operators
β Scribed by Jaak Peetre
- Publisher
- John Wiley and Sons
- Year
- 1961
- Tongue
- English
- Weight
- 397 KB
- Volume
- 14
- Category
- Article
- ISSN
- 0010-3640
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π SIMILAR VOLUMES
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