If the primary content is musical notation — even when accompanied by lyrics and chord symbols — the article generally classifies under 4904. A publication that is predominantly text (such as a biography of a musician with only incidental notation) would fall under 4901. The essential character of the publication's content drives the classification.

Yes, provided the content is musical in nature. The heading covers music 'printed or in manuscript,' and a facsimile or high-quality reproduction of a historical musical manuscript printed commercially still qualifies under 4904. The format of reproduction does not disqualify the article as long as the subject matter is music.