Assertion: zeppelin's album | /r/CapableOf | include many of song
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Source sentences:
text: Although acoustic and folk-based music was part of the band’s repertoire from its inception, it was the bottom-heavy, loud, raw, and powerful electric style that gained them their following and notoriety early on; their first two albums included many of the songs that prompted Led Zeppelin’s categorization as a precursor of heavy metal.