The latest one resolved was minimum-weight triangulation, proved to be NP-complete in 2008. Mulzer, Wolfgang; Rote, Günter (2008), «Minimum-weight triangulation is NP-hard», Journal of the ACM, 55 (2), doi:10.1145/1346330.1346336, Arxiv.
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The latest one resolved was minimum-weight triangulation, proved to be NP-complete in 2008. Mulzer, Wolfgang; Rote, Günter (2008), «Minimum-weight triangulation is NP-hard», Journal of the ACM, 55 (2), doi:10.1145/1346330.1346336, Arxiv.