Institution, 8. B. S. (1990). Cross recesses for screws. London : British Standards Institution.
Chicago-viite (17. p.)Institution, 8096 British Standards. Cross Recesses for Screws. London : British Standards Institution, 1990.
MLA-viite (9. p.)Institution, 8096 British Standards. Cross Recesses for Screws. London : British Standards Institution, 1990.
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