Production Gas (hereinafter, Gas), an anonymous artist group that was active in Nagoya from 1969 to 1974, released a 7-inch LP record, Gas’ Disk, in 1970. It includes four songs; “Gas no Theme (Gas’ Theme),” “Uta (Song),” “Proo” and “Hiren (Sad Love),” and the group name and title was branded on the wooden jacket. This type of self-produced record was referred to as “private record,” “angura (underground) record” or “personal record” at that time. The members contributed money to press 1,000 cop…