The liner note writer uses a note to Ed Michel, Impulse records and they are written in the present tense, late 1966/early 1967. Surely that should have been corrected?
Michel was on or about ABC in 1966, so "Riverside" seems an arbitrary choice of label. So does impulse! For that matter!
I have several ABC/Riverside records, but they're all reissues. This one is definitely an anomaly.
Ok, his LinkedIn profile has this on his resume:
Staff Producer, Director of International Operations
Riverside Records
1961 - 1964 3 years
But that gig ended in 1964....