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[Subject: Precision & Other Instruments]
Translated in 8 languages
Translated in 6 languages
[Subject: Athletic & Outdoor Sports & Games]
Translated in 4 languages
[Subject: General Technologies]
[Subject: Earth (Astronomical Geography)]
[Subject: Hydraulic Engineering]
Translated in 2 languages
[Subject: Building Materials]
[Subject: Metal Manufactures]
[Subject: Mechanics]