Some remarks on almost-positivity of ψ do 's

Cesare Parenti; Alberto Parmeggiani

Bollettino dell'Unione Matematica Italiana (1998)

  • Volume: 1-B, Issue: 1, page 187-215
  • ISSN: 0392-4041

How to cite


Parenti, Cesare, and Parmeggiani, Alberto. "Some remarks on almost-positivity of $\psi\text{do}$'s." Bollettino dell'Unione Matematica Italiana 1-B.1 (1998): 187-215. <>.

author = {Parenti, Cesare, Parmeggiani, Alberto},
journal = {Bollettino dell'Unione Matematica Italiana},
keywords = {almost positivity; Hörmander’s inequality},
language = {eng},
month = {2},
number = {1},
pages = {187-215},
publisher = {Unione Matematica Italiana},
title = {Some remarks on almost-positivity of $\psi\text\{do\}$'s},
url = {},
volume = {1-B},
year = {1998},

AU - Parenti, Cesare
AU - Parmeggiani, Alberto
TI - Some remarks on almost-positivity of $\psi\text{do}$'s
JO - Bollettino dell'Unione Matematica Italiana
DA - 1998/2//
PB - Unione Matematica Italiana
VL - 1-B
IS - 1
SP - 187
EP - 215
LA - eng
KW - almost positivity; Hörmander’s inequality
UR -
ER -


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  13. PARENTI, C.- PARMEGGIANI, A., Lower bounds for pseudodifferential operators, in Proceedings N.A.T.O. Conference in Microlocal Analysis and Spectral Theory, L. Rodino (ed.), Vol. 490, Kluwer Academic Publisher (1997), 251-262. Zbl0881.35132MR1451395
  14. PARMEGGIANI, A., Necessary and sufficient conditions for the almost-positivity of certain 4th-order pseudodifferential operators, to appear in Forum Mathematicum. Zbl0927.35140
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