Hiromi Sawai, Hiroto Otani, Nobuko Arisue, Nirianne Palacpac, Sisira Pathirana, Shiroma Handunnetti, Leonardo de Oliveira Martins, Satoru Kawai, Hirohisa Kishino, Toshihiro Horii, and Kazuyuki Tanabe. Lineage-specific Positive Selection at the Merozoite Surface Protein 1 (msp1) Locus of Plasmodium vivax and related Simian Malaria Parasites. BMC Evolutionary Biology 2010, 10:52.  doi:10.1186/1471-2148-10-52