On degenerate boundary value problems for elliptic differential operators of second order in the plane and the index of degenerate pseudo-differential operators on a closed curve
1981 ◽
Vol 102
(1)
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pp. 277-292
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2018 ◽
Vol 39
(2)
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pp. 289-296
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1985 ◽
Vol 121
(1)
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pp. 71-106
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2008 ◽
Vol 51
(2)
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pp. 315-335
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1995 ◽
Vol 123
(8)
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pp. 2519-2519
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