Approximation by Fourier sums of classes of periodic functions of several variables defined by polyharmonic operators
1981 ◽
Vol 17
(2)
◽
pp. 369-403
◽
2004 ◽
Vol 195
(2)
◽
pp. 237-261
◽
1986 ◽
Vol 27
(2)
◽
pp. 219-237
◽
1998 ◽
Vol 50
(2)
◽
pp. 314-333
◽
1986 ◽
Vol 27
(2)
◽
pp. 285-322
◽
2015 ◽
Vol 66
(8)
◽
pp. 1248-1266
◽
1988 ◽
Vol 4
(4)
◽
pp. 356-372
◽