We construct a counter example to the Besicovitch covering property for some class of Carnot groups equipped with their Carnot - Caratheodory metric. The construction uses some regularity assumptions for minimal geodesics and for the distance function to the origin. As an example we show that groups of type H, thus including all Heisenberg groups, satisfy these assumptions. We prove in particular that, in groups of type H, the distance function to the origin is Pansu-differentiable outside the center with continuous Pansu-differential there.
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