...forthcoming from Chandos:
http://www.mdt.co.uk/pierne-gabriel-orchestra-works-2-juanjo-mena-chandos.html (http://www.mdt.co.uk/pierne-gabriel-orchestra-works-2-juanjo-mena-chandos.html)
Odd they have a couple solo piano pieces, not to mention much of it is for piano and orchestra (all recorded on the Hyperion disc from the RPC series).
Les Cathédrales is new to me though, as is the Nocturne. Hmmm.....
Here's a score to Les cathédrales (http://imslp.org/wiki/Les_cath%C3%A9drales_%28Piern%C3%A9,_Gabriel%29) for optional chorus and orchestra as published in 1916 by Rouart L&C (and scanned in by Sibley Library, U. Rochester in NY, mirrored by IMSLP.)
(Could the nocturne be another orchestration? He wrote at least one, his op.31 pub. in 1897, for piano solo...)
The credits on the page imply the last two pieces are for solo piano (look at the * and the †)