@techreport{oai:kumadai.repo.nii.ac.jp:00022364,
 author = {Komoto, Masayuki and 甲元, 眞之},
 month = {Mar},
 note = {application/pdf, 研究報告書, In the Ryukyu Islands it is clear that cereal cultivation had begun by the Gusuku Period (12-15th centuries AD). In this paper, I examine the beginning of cereal cultivation based upon archaeological materials. Prior to the Gusuku period, the cereal remains obtained from three sites (Nazakibaru, Yajagama and Nagarabaru-Higashi) are rice, wheat, barley and beans. All of these were discovered in a carbonized state, a condition that is often produced by the process of threshing. These cereals thus tell us that cultivation had already began at the end of the first millennium in the Ryukyu Islands. In addition, these cereals are thought to be derived from dry field cultivation and it is very important that this type of cultivation was connected directly with that of the Ryukyu Dynasty.},
 title = {琉球列島の農耕のはじまり},
 year = {2003}
}