Abstract
We prove that a terminal three-dimensional del Pezzo fibration has no fibers of multiplicity >6. We also obtain a rough classification of possible configurations of singular points on multiple fibers and give some examples.
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To the memory of Professor Vasily Alekseevich Iskovskikh
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Mori, S., Prokhorov, Y. Multiple fibers of del Pezzo fibrations. Proc. Steklov Inst. Math. 264, 131–145 (2009). https://doi.org/10.1134/S0081543809010167
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DOI: https://doi.org/10.1134/S0081543809010167