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    Journal = {AN},
    Title = {},
    Pages = {1},
    Volume = {322},
    Year = {2001}}

@article{bib2,
    Author = {E. F. Author3 and G. H. Author4},
    Journal = {AN},
    Title = {},
    Pages = {10},
    Volume = {322},
    Year = {2001}}

@article{bib3,
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    Journal = {AN},
    Title = {},
    Pages = {20},
    Volume = {322},
    Year = {2001}}

@article{bib4,
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    Journal = {AN},
    Title = {},
    Pages = {30},
    Volume = {322},
    Year = {2001}}
