File:Aria Diamond series Model 5120 by Matsumoku (SN 0728021) (1970-1974) hollow-body bass guitar - a bolt-on neck joint with a plate on which serial number was engraved (2013-01-16 17.18.13 by basstpm).jpg - Wikimedia Commons
How Old Is My Guitar? Use the Serial Number! | George's Music
How Old Is My Guitar? Use the Serial Number! | George's Music