• BS 3692 2014 ISO metric precision hexagon bolts, screws and nuts. Specification.pdf
• AWS A1.1-2016 Metric Practice Guide for the Welding Industry.pdf
• JIS B2292-1-2005 Hydraulic fluid power-Dimensions and identification code for mounting flanges and shaft ends of displacement pumps and motors-Part 1：Inch series shown in metric units.pdf