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MR 0236740 |
Zbl 0172.17501
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On the method of least squares of finding eigenvalues and eigenfunctions of some symmetric operators. Comment. Math. Univ. Carolinae 11 (1970), 449-462.
MR 0276807 |
Zbl 0211.16402
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Error - estimates for the method of least squares of finding eigenvalues and eigenfunctions. Comment. Math. Univ. Carolinae 11 (1970), 463-479.
MR 0276808 |
Zbl 0211.16501
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