@misc{oai:serve.repo.nii.ac.jp:00002910,
 author = {Koyano , Wataru and Koyano , Wataru},
 month = {Jul},
 title = {Geographical distance and frequency of contacts between elderly parents and children in Japan.},
 year = {2001},
 yomi = {コヤノ, ワタル}
}