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We present a tableau-based decision procedure for the fusion (independent join) of the expressive description logic \(\mathcal{ALCQO}\) and the logic \(\mathcal{MS}\) for reasoning about distances and similarities. The resulting ‘hybrid’ logic allows both precise and approximate representation of and reasoning about concepts. The tableau algorithm combines the existing tableaux for the components and shows that the tableau technique can be fruitfully applied to fusions of logics with nominals—the case in which no general decidability transfer results for fusions are available.