Michael Haydn's Symphony No. 34 in E-flat major, Perger 26, Sherman 34, MH 473, written in Salzburg in 1788, is the last E-flat major symphony he wrote, the first of his final set of six symphonies.
The first and last movements begin the same way, only that the first movement uses the theme to launch a sonata form while the third movement uses it to preface a fugato.
A. Delarte, "A Quick Overview Of The Instrumental Music Of Michael Haydn" Bob's Poetry Magazine November 2006: 28 - 29 PDF
Charles H. Sherman and T. Donley Thomas, Johann Michael Haydn (1737 - 1806), a chronological thematic catalogue of his works. Stuyvesant, New York: Pendragon Press (1993)
C. Sherman, "Johann Michael Haydn" in The Symphony: Salzburg, Part 2 London: Garland Publishing (1982): lxviii