@article{oai:repository.dl.itc.u-tokyo.ac.jp:00033356,
 author = {Yokoyama, Izumi and Hadikusumo, Djajadi},
 issue = {5},
 journal = {東京大學地震研究所彙報 = Bulletin of the Earthquake Research Institute, University of Tokyo},
 month = {Nov},
 note = {application/pdf},
 pages = {991--1001},
 title = {45. Volcanological Survey of Indonesian Volcanoes : Part 3. A Gravity Survey on the Krakatau Islands, Indonesia},
 volume = {47},
 year = {1969}
}