Horai, Satoshi and Omoto, Keiichi and Juji, Takeo and Sonozaki, Hidekichi and Mitsui, Hiroshi and Misawa, Shogo and Sumpaico, Joaquin S. and Mercado, Alfredo S. (2008) The HLA Antigens of Two Negrito Populations in the Philippines. Tissue Antigens, 17 (3). pp. 343-348.
Omoto, Keiichi and Ueda, Shintaro and Goriki, Kazuaki and Takahashi, Norio and Misawa, Shogo and Pagaran, Ildefonso G (1981) Population genetic studies of the Philippine Negritos. III. Identification of the carbonic anhydrase-1 variant with CA1 Guam. American journal of human genetics, 33 (1). p. 105.