Polymorphisms in Pvkelch12 and gene amplification of Pvplasmepsin4 in plasmodium vivax from Thailand, Lao PDR and Cambodia by Duanguppama, J, Mathema, V, Tripura, R, Day, N, Nguon, C, Maxay, M, Von Seidlein, L, Dhorda, M, Peto, T, Nosten, F, White, N, Dondorp, A, Imwong, M