Surfaces with $p_g = 0$, $K^2 = 5$ and bicanonical maps of degree 4
arXiv:1011.1061
Abstract
Let $S$ be a minimal surface of general type with $p_g(S) = 0, K_S^2 = 5$ and bicanonical map of degree 4. Denote by $Σ$ the bicanonical image. If $Σ$ is smooth, then $S$ is a Burniat surface; and if $Σ$ is singular, then we reduced $Σ$ to one case and described it, furthermore $S$ has at most one $(-2)$-curve.
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