Denny Zeitlin LP-Soundings/ Free Improvisations Solo Piano-1750 Arch Records

The inner sleeve is either plastic or cellophane. The gentleman had his own filing system of his collection & every sleeve and/or box is labeled. You can see that label in the photos that I've uploaded.

Pianist Zeitlin marks first album's 50th anniversary – The Mercury News

Precipice Denny Zeitlin

Y / Denny Zeitlin LP-Soundings/ Free Improvisations Solo Piano

Denny Zeitlin: Nothing Halfway article @ All About Jazz

Denny Zeitlin LP-Soundings/ Free Improvisations Solo Piano-1750 Arch Records

Denny Zeitlin – Soundings (1978, Vinyl) - Discogs

Denny Zeitlin - Solo

Grateful Dead Family Discography: Keystone Korner Discography

Bill Dobbins - The Contemporary Jazz Pianist - Vol. 4, PDF, Jazz Music

Record Collector Issue 523 October 2021, PDF

Jazz Record Revival - Zeitlin, Denny - Solo Voyage

OUT-OF-PRINT JAZZ LP LIST! SOME RARE - Delmark Records