We give a time regularity result for an abstract mixed type equation whose toy model may be where is a coefficient whose sign may be positive, null and negative.
@article{BUMI_2011_9_4_1_69_0, author = {Fabio Paronetto}, title = {A Time Regularity Result for Forward-Backward Parabolic Equations}, journal = {Bollettino dell'Unione Matematica Italiana}, volume = {4}, year = {2011}, pages = {69-77}, zbl = {1234.35052}, mrnumber = {2797466}, language = {en}, url = {http://dml.mathdoc.fr/item/BUMI_2011_9_4_1_69_0} }
Paronetto, Fabio. A Time Regularity Result for Forward-Backward Parabolic Equations. Bollettino dell'Unione Matematica Italiana, Tome 4 (2011) pp. 69-77. http://gdmltest.u-ga.fr/item/BUMI_2011_9_4_1_69_0/
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