SCI Science Citation Index 1980 annual : part 11 permuterm subject index Diff-Leaf
Institute fo Scientific Information, 1981
 Buku Referensi
SCI Science Citation Index 1980 annual : part 12 permuterm subject index Leaf-Rand
Institute fo Scientific Information, 1981
 Buku Referensi
SCI Science Citation Index 1980 annual : part 10 permuterm subject index A-Diff
Institute fo Scientific Information, 1981
 Buku Referensi
Science
American Association for the Advancement of Science, 2018
 Majalah, Jurnal, Buletin
Combined science
Geoff Green, Ken Petford, Alan Short, David Walker
John Muray, 1975
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