@article{oai:nipr.repo.nii.ac.jp:00002208,
 author = {Wumkes, M. A.},
 journal = {Memoirs of National Institute of Polar Research. Special issue},
 month = {Mar},
 note = {P(論文), The development of the 13.2cm (5.2 inch) U. S. deep coring ice drill has required new approaches to the drill operation and handling. Large diameter cores 6m (20 feet) long have dictated a change in the scope of not only the drill handling but core handling as well. A drill handling system has been designed and refined to accommodate these large cores. New drilling fluids have re-defined operational procedures in regards to safety and environmental concerns. These new drilling fluids have also forced investigators to incorporate recycling procedures due to the high costs of the drilling fluid. These and other factors are discussed as related to drilling operational requirements.},
 pages = {52--56},
 title = {Operational considerations of the U. S. deep coring ice drill},
 volume = {49},
 year = {1994}
}