Clavier, modulations before or after stretto entries are easily accomplished. Prelude and Fugue in G minor (BWV 558) In 1931, it was suggested by the musicologist Fritz Dietrich that the prelude could technically be regarded as an "Italian courante", but, as Williams points out, that runs counter to the ABAB form and the change of harmony in every bar. The conventional formulaic cadences and simple one-bar sequences over a basso continuo seem like a composer "consciously creating a series of samples". The subject of the fugue is composed of three separate motifs, all of which can be found in canzonas and ricercars. The 19th-century Bach scholar Philipp Spitta praised the fugue, particularly its modulations. Williams has suggested that "perhaps the imaginative penultimate bar was inspired by J. S. Bach". Prelude and Fugue in A minor (BWV 559) The little Prelude and Fugue in A minor, BWV 559 lies in the shadows of Bach's celebrated Prelude and Fugue in A minor, BWV 543. The demisemiquaver passagework of the little prelude is typical of toccata organ writing in Southern Germany, although they can also be found in Dieterich Buxtehude's works; the use of pedal points in BWV 559 indicate techniques of organ writing already heard in BWV 543. Like the fugue in BWV 543, the second half of the subject of the fugue in BWV 559 is ornamented; otherwise, however, it is composed on a quite different scale, being more like the "verset-fughettas" of Fischer. Prelude and Fugue in B-flat major (BWV 560) According to Williams, the musical style of the prelude is reflected in contemporary oboe concertos of the 1730s; while the fugue was probably composed after 1740 and shows the influence of Handel's Concerti grossi. Selected recordings Organ Marie-Claire Alain, reissue, 2011, Erato Records. Ton Koopman, Garrels organ, Groote Kerk, Maassluis, 1990, Novalis. Simon Preston, 1996, Decca Records. Peter Hurford, recording on period German organs, 1995, Decca Records. Kevin Bowyer, Skt. Hans Kirke, Odense, 1991, Nimbus Records. John Keys, 2012, ASIN: B0087WIV1S. Hans Fagius, 2007, BIS Records. Hans Helmut Tillmanns, on the Weimbs organ in Widdersdorf, Cologne, 2003, Danacord, DACOCD 608. Robert Köbler, Organ Works on Silbermann Organs, Vol. 7, 1998 (reissue), Berlin Classics. Gerhard Weinberger, Carl Christian Hoffmann Organ, St. Marien, Mechterstädt, 2008, CPO 777 363-2. Hans Vollenweider, Reformierte Kirche, Schönenberg, Zürich, 1997, Tudor. Wolfgang Stockmeier, Kirche Maria Himmelfahrt, Lorup, reissue, 2007, Membran. Piet Kee, organ of St Bavo