who are the members of the later band mentioned above?
Syd Barrett, Nick Mason, Roger Waters, and Richard Wright, and David Gilmour
Pink Floyd
Pink Floyd were founded by students Syd Barrett (guitar, lead vocals), Nick Mason (drums), Roger Waters (bass guitar, vocals), and Richard Wright (keyboards, vocals). Under Barrett's leadership, they released two charting singles and a successful debut album, "The Piper at the Gates of Dawn" (1967). Guitarist and vocalist David Gilmour joined in December 1967; Barrett left in April 1968 due to deteriorating mental health. 
who is laughing in dark side of the moon Peter Watts who was he? An English road manager and sound engineer which bands was he a manager for? The Pretty Things and Pink Floyd
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Pink Floyd [SEP] Introduction
The band produced two more albums—"A Momentary Lapse of Reason" (1987) and "The Division Bell" (1994)—and toured both albums before entering a long period of inactivity. In 2005, all but Barrett reunited for a one-off performance at the global awareness event Live 8. Barrett died in 2006, and Wright in 2008. The last Pink Floyd studio album, "The Endless River" (2014), was based on unreleased material from the "Division Bell" recording sessions.