Document Type and Number:
Japanese Patent JPS568988
Kind Code:
Y2
Application Number:
JP7578377U
Publication Date:
February 27, 1981
Filing Date:
June 10, 1977
Export Citation:
International Classes:
E02D3/10; E02D19/00; E02D31/00; E21B7/00; (IPC1-7): E02D3/10
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