Allen Anders Seipt
http://www.worldcat.org/title/schwenkfelder-hymnology-and-the-sources-of-the-first-schwenkfelder-hymn-book-printed-in-america/oclc/285513
1909
https://archive.org/details/schwenkfelderhym00seip
Probably republished around 1971 according to the Worldcat record. Introduction.--Descriptive bibliography (p. 17-36)--The Schwenkfelder hymn-writers of the 16th and 17th centuries.--Hymns used by the Schwenkfelders before 1762.--Caspar Weiss: the originator of the Schwenkfelder hymn-book.--George Weiss: writer and compiler of hymns.--Balthaser Hoffmann, Christopher Hoffmann, and Hans Christoph Huebner.--Christopher Schultz and the printed hymn-book.--Bibliography (p. 111-112)