Abstract
We prove that every oriented graph with a maximum average degree less than 18/7 admits a homomorphism into $$P_{7}^{*}$$P7?, the Paley tournament of order seven with one vertex deleted. In particular, every oriented planar graph of girth at least 9 has a homomorphism into $$P_{7}^{*}$$P7?, whence every planar graph of girth at least 9 has oriented chromatic number at most 6.
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