@article{oai:repository.dl.itc.u-tokyo.ac.jp:00038659,
 author = {Nagaoka, H.},
 journal = {Publications of the Earthquake Investigation Committee in foreign languages},
 month = {Feb},
 note = {application/pdf},
 pages = {47--67},
 title = {Elastic Constants of Rocks and the Velocity of Seismic Waves},
 volume = {4},
 year = {1900}
}