There are 106 symphonies by the classical composer Joseph Haydn (1732–1809). Of these, 104 have numbers associated with them which were originally assigned by Eusebius Mandyczewski in 1908 in the chronological order that was known at the time.[1] In the subsequent decades, numerous inaccuracies in the chronology (especially in the lower numbers) were found, but the Mandyczewski numbers were so widely used that when Anthony van Hoboken compiled his catalogue of Haydn's works, he incorporated the Mandyczewski number into Catalogue I (e.g., Symphony No. 34 is listed as Hob. I/34).[1] Also in that time period, two additional symphonies were discovered (which were assigned non-Mandyczewskian letters "A" and "B"), bringing the total to 106.