Hans Sitt, (1850 – 1922) was a Bohemian violinist, violist, teacher, and composer. He wrote several books with etudes & exercises. Here a selection from a serie of books with Technical etudes from Opus 92.
You can find all the original sheet music of Hans Sitt (any many others) on the IMSLP Petrucci Music Library
Hans-Sitt-Technical-Studies-Op.-92