Royan-gi
So I was reading Ann Hutchison Guest's Dance Notation (1984) and found, as an example of an "avant-garde composer[...] indicat[ing] duration by length" an excerpt from "The Garden of Royan-gi by Louis Andriesson, 1967".
I found that title intriguing and suspicious, and indeed it appears to be a typo for The Garden of Ryoan-gi, i.e. Ryōan-ji. The work was apparently for three electronic organs, and 1967 is a decade and a half before Cage's famous take on the same theme.
There's no performance of The Garden of Ryoan-gi available online as far as I can tell (although Andriessen himself has a blog), but I did find a nice performance of Cage's piece by Liz Tonne (voice) and Tim Feeney (percussion). If you want to follow a score for the percussion part, you'll find one on the first page of this transcript of a 1983 conversation between Cage and Morton Feldman.