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@book{CoddingtonLevinson:1984,
    title = {Theory of ordinary differential equations},
    author = {Earl A. Coddington, Norman Levinson},
    publisher = {R. E. Krieger},
    isbn = {9780898747553,0898747554},
    year = {1984},
    series = {},
    edition = {},
    volume = {},
    url = {http://gen.lib.rus.ec/book/index.php?md5=e9aae04b756f9be78d30eadab8f55d05},
    date-added = {2024-1-20 11:11:29 +0100}
}

@book{CoddingtonLevinson:1984, title = {Theory of ordinary differential equations}, author = {Earl A. Coddington, Norman Levinson}, publisher = {R. E. Krieger}, isbn = {9780898747553,0898747554}, year = {1984}, series = {}, edition = {}, volume = {}, url = {http://gen.lib.rus.ec/book/index.php?md5=e9aae04b756f9be78d30eadab8f55d05}, date-added = {2024-1-20 11:11:29 +0100} }