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Variations on Van Kampen's method

David Bessis
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Abstract

We give a detailed account of the classical Van Kampen method for computing presentations of fundamental groups of complements of complex algebraic curves, and of a variant of this method, working with arbitrary projections (even with vertical asymptotes).

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David Bessis. 2003-01-28. Variations on Van Kampen's method. https://arxiv.org/abs/math/0301327

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