Gary Holton: A unified system of spatial orientation in the Austronesian and non-Austronesian languages of Halmahera. W: Antoinette Schapper (red.): Contact and substrate in the languages of Wallacea. Cz. 1. 2017, s. 157–189, seria: NUSA: Linguistic studies of languages in and around Indonesia 62. DOI: 10.15026/89846. OCLC1017738888. (ang.).
Robert Blust: Eastern Malayo-Polynesian: A Subgrouping Argument. W: Stephen Adolphe Wurm, Lois Carrington (red.): Second International Conference on Austronesian Linguistics: Proceedings. Canberra: Department of Linguistics, Research School of Pacific Studies, Australian National University, 1978, s. 181–234, seria: Pacific Linguistics C-61. DOI: 10.15144/PL-C61.181. ISBN 978-0-85883-184-1. OCLC499358051. (ang.).
Gary Holton: A unified system of spatial orientation in the Austronesian and non-Austronesian languages of Halmahera. W: Antoinette Schapper (red.): Contact and substrate in the languages of Wallacea. Cz. 1. 2017, s. 157–189, seria: NUSA: Linguistic studies of languages in and around Indonesia 62. DOI: 10.15026/89846. OCLC1017738888. (ang.).
Robert Blust: The Austronesian Languages. Canberra: Pacific Linguistics, Research School of Pacific and Asian Studies, Australian National University, 2009, s. 652, seria: Pacific Linguistics 602. ISBN 978-0-85883-602-0. OCLC320478203. (ang.).
Robert Blust: Eastern Malayo-Polynesian: A Subgrouping Argument. W: Stephen Adolphe Wurm, Lois Carrington (red.): Second International Conference on Austronesian Linguistics: Proceedings. Canberra: Department of Linguistics, Research School of Pacific Studies, Australian National University, 1978, s. 181–234, seria: Pacific Linguistics C-61. DOI: 10.15144/PL-C61.181. ISBN 978-0-85883-184-1. OCLC499358051. (ang.).