See
http://www.ebay.co.uk/itm/Aircraft-Hardware-Standards-Manual-Stanley-Dzik-c-1977/291536624744?_trksid=p2045573.c100033.m2042&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D29974%26meid%3Dda22f11acf9e4c098baebd764de4877d%26pid%3D100033%26rk%3D2%26rkt%3D4%26mehot%3Des%26sd%3D331627203254