"Slipped Through Heaven" uses an unreleased piano phrase from Spirit Of Peace IV by Popol Vuh, courtesy Johannes Fricke Waldthausen/Edition Popol Vuh.
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Joseph D.Rowland (Pallbearer):
"Popol Vuh is one of my favorite bands of all time. I'm not really sure how I came across Popol Vuh years ago, but they have consistently stuck with me as one of the most atmosphere-filled music groups that's able to conjure up such an incredible feeling, a meditative feeling, with simple but with awesome melodies, hypnotic". (2013)