@techreport{oai:kumadai.repo.nii.ac.jp:00022368,
 author = {Kurozumi, Taiji and 黒住, 耐二},
 month = {Mar},
 note = {application/pdf, 研究報告書, Analyses such as species composition and abundance and size of some species of marine molluscan remains excavated from shell middens of the 6th to 8th centuries in the central Ryukyus showed that (1) coral reef species were most dominant, and (2) large- and small-sized molluscs were used in a different manner. Large species might have been utilized for their meat, small species for "soup". Cultivation seems not to have existed in this region at that time because (1) open land dwelling snails associated with dry fields were very rare or absent, and (2) the fresh water snail Chipangqpaludina chinensis laeta which inhabits paddy fields was not found. In the Gusuku era, on the other hand, species dwelling in inland sea and estuary areas dominated the edible marine molluscan remains. The change in mollusc composition must have therefore occurred by at least the 12th century.},
 title = {貝類遺体からみた奄美・沖縄の自然環境と生活},
 year = {2003}
}