On regularity of solutions to systems of partial differential equations which are locally close to elliptic systems of linear equations with constant coefficients. I
1962 ◽
Vol 38
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pp. 587-590
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2007 ◽
pp. 137-153
1994 ◽
Vol 24
(3-4)
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pp. 219-231
2004 ◽
Vol 166
(1)
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pp. 181-208
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