Procol Harum is the eponymous debut studio album by the English rock band. Originally released in 1967 it now celebrates it's 50th year anniversary. Though the album was recorded on multi-track, it was issued as mono-only in the U.K. All songs were originally credited written to Gary Brooker (music) and Keith Reid (lyrics), except "Repent Walpurgis" written by Matthew Fisher, after works by French organist Charles-Marie Widor and German composer Johann Sebastian Bach.