Middle-period Sources [ii]

By comparison with the relatively large number of pre-1630 and post-1650 sources, few manuscripts can be allocated to the middle period. However, this period includes not only by far the most important single source for Heinrich Scheidemann's organ music which — apart from the early autographs — is the only source which may show traces of the composer's personal involvement. The some Scheidemann entries belong to the earliest testimonies of his copying style so familiar from his famous huge collection of vocal and instrumental ensemble music kept by the same library. The two Scheidemann entries belong to the earliest testimonies of his copying style so familiar from his famous huge collection of vocal and instrumental ensemble music kept by the same library. The assumption that Gustav Duben wrote out this piece and the praeambulum directly from the autographs and under the composer's supervision is supported by their near-impeccable texts and the presence of the familiar composition dates.