Regarding the "Unknown Sonata" on this page.
This indeed is not Sonata no. 5 of L'Echo du Danube. However, it is Sonata no. 5 in the manuscript source cited from the Österreichischen National Bibliothek.
The same manuscript also has as its Sonata no. 4 a sonata in A minor that corresponds in some movements with Sonata no. 6 of L'Echo du Danube, but differs in other movements.
Both of these manuscript sonatas were published along with the whole of L'Echo du Danube in Das Erbe Deutscher Musik vol. 67 (1973), edited by Karl Heinz Pauls.
The other sonatas in the manuscript are identical to sonatas in L'Echo du Danube.
The manuscript can be consulted online and downloaded from the library at http://data.onb.ac.at/dtl/2414739
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Unknown Sonata (from manuscript source)
Complete Score
#336433 - 0.57MB, 6 pp. - 246810 (0) -
Editor Markus Kroell
Misc. Notes Source: Manuscript Nr.16598 der Österreichischen National Bibliothek Wien (ÖNB). This is not Sonata No.5.
L'écho du Danube, Op.9 (Schenck, Johann)
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