arXiv · math/0104208
We find all three-dimensional Einstein--Weyl spaces with the vanishing scalar curvature
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David M. J. Calderbank, Maciej Dunajski. 2001-04-22. Scalar--Flat Lorentzian Einstein--Weyl Spaces. https://doi.org/10.1088/0264-9381%2F18%2F14%2F101
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