LiquiGlide is a high-tech coating that, when applied to a container renders it effectively friction-free.

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Greece can at least point to a relatively harmonious relationship with Bulgaria, to its north-east, although the presence of Slavic-speaking Bulgarian ethnic kin in northern Greece has not been friction-free.

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Not that such swaps are friction-free.

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WTO, is causing friction between free-traders and defenders of ideas such as environmentalism and human rights.

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